2020 - Repozytorium publikacji - Politechnika Gdańska

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Interpretation and modeling of emotions in the management of autonomous robots using a control paradigm based on a scheduling variable
- Zdzisław Kowalczuk
- Michał Czubenko
- Tomasz Merta
2020 Pełny tekst ENGINEERING APPLICATIONS OF ARTIFICIAL INTELLIGENCE
The paper presents a technical introduction to psychological theories of emotions. It highlights a usable ideaimplemented in a number of recently developed computational systems of emotions, and the hypothesis thatemotion can play the role of a scheduling variable in controlling autonomous robots. In the main part ofthis study, we outline our own computational system of emotion – xEmotion – designed as a key structuralelement in the developed target device, being an Intelligent System of Decision-making (ISD) for autonomousand robotic units.The ISD system has a cognitive architecture based on the principles of human psychology. The mainpurpose of building such a system is to prepare a framework for autonomous units used in system engineering(Kowalczuk and Czubenko, 2011; Czubenko et al., 2015). In particular, ISD is based on the concepts ofcognitivepsychology(in information processing) andmotivation theory, which includes the system ofneeds(for decision-making). The xEmotion subsystem, however, focuses on modeling an alternative approach based on emotion.The xEmotion implementation covers aspects of somatic, appraisal and evolutionary theories of emotions usingfuzzy sets.In this article, we also illustrate the core emotional behavior of the ISD system using simulation. Thefirst application is a user interface for identifying emotions and predicting human behavior. The second is aneSailor simulation, which illustrates the possible behavior of the xEmotion subsystem. The last is an xDriversimulation experiment, which is to prove the validity of the concept of using emotion-based systems, accordingto the SVC principle. In summary, we also discuss other possible applications of the xEmotion system.
Interrelations between Travel Patterns and Urban Spatial Structure of the Largest Russian Cities
- Ekaterina Saveleva
2020
The study presented within this dissertation involves the analysis of the relationship between urban spatial structure and travel patterns in the largest Russian cities. It is an empirical investigation of how the spatial structure, formed during the Soviet and post-Soviet periods, affects the travel patterns in the largest cities of contemporary Russia. It aims to determine what measures, both urban structure and transportation related, are suitable for such urban form to introduce most sustainable mobility patterns. The dissertation examines in detail how urban form and travel are interlinked, and how mobility patterns are created through many factors, not the last of which is the built environment. It provides a review of theoretical model of interaction between urban form and travel patterns followed by the empirical analysis of the link between urban spatial structure and travel patterns performed on a sample of the 13 largest Russian cities. The result of the GIS-based spatial analysis of the Russian cities‘ urban morphology comes in the form of quantitative dataset of various urban form characteristics, which are further used for the exploration of the interrelation between them and travel patterns in the largest Russian cities. Building on the findings regarding travel and urban form relationship in the largest Russian cities, the dissertation proposes both general directions for the development of cities with Soviet past and particular recommendations for the largest Russian cities, taking into account the current mobility situation, the specificities of their urban structure and the influence it has on the travel patterns.
Invasive Assessment of the Myocardial Microcirculation during Beating Heart Coronary Artery Bypass Grafting
- Mariusz Kaszubowski
- Marcin Hellmann
2020 Pełny tekst Journal of Clinical Medicine
Coronary artery bypass grafting may be associated with several cardiac complications, including ischemia, acute myocardial infarction, arrhythmias, or hemodynamic instability. Accumulating evidence suggests that well-developed coronary collateral circulation may protect against adverse effects, including myocardial ischemia. Assessment of myocardial microvascular perfusion is, therefore, of great clinical interest in beating heart surgery. In this paper, myocardial microvascular perfusion is continuously assessed on the beating heart using laser Doppler flowmetry in consecutive patients who underwent coronary artery bypass grafting procedures. No significant (p = 0.110) differences were found between the averaged perfusion signal (n = 42) at the baseline, during artery occlusion, or after reperfusion (732.4 ± 148.0 vs. 711.4 ± 144.1 vs. 737.0 ± 141.2, respectively). In contrast, significantly different (p < 0.001) mean perfusion signals (n = 12) were found (805.4 ± 200.1 vs. 577.2 ± 212.8 vs. 649.3 ± 220.8) in a subset of patients who presented with hemodynamic instability and myocardial ischemia. Additionally, a strong positive correlation between the plasma levels of high-sensitivity troponin I and perfusion decrease level after artery occlusion was found (r = 0.854, p < 0.001). This study argues that myocardial microvascular perfusion remains constant during coronary artery bypass grafting on the beating heart in advanced coronary artery disease. This phenomenon is most likely due to an extensive coronary collateral circulation.
Inverse Analysis as a Key Element of Safety Assessment under the Snow Load For The Large Suspension Roofs Structure
- Krzysztof Żółtowski
- Michał Drawc
2020 Pełny tekst Archives of Civil Engineering
The paper presents a concept and realization of monitoring system for the Silesian Stadium in Chorzow. The idea of the system lies in fusion of structure monitoring with a calibrated numerical FEM model [1]. The inverse problem is solved. On the base of measured selected displacements, the numerical FEM model of the structure combined with iterative method, develops the current snow load distribution. Knowing the load, we can calculate the forces and stresses in each element of the structure and thanks to this we can determine the safety thresholds and asses the owner. Test results and conclusions are presented
Inverse shadowing and related measures
- Sergey Kryzhevich
- Sergei Pilyugin
2020 Pełny tekst Science China-Mathematics
We study various weaker forms of the inverse shadowing property for discrete dynamical systems on a smooth compact manifold. First, we introduce the so-called ergodic inverse shadowing property (Birkhoff averages of continuous functions along an exact trajectory and the approximating one are close). We demonstrate that this property implies the continuity of the set of invariant measures in the Hausdorff metric. We show that the class of systems with ergodic inverse shadowing is quite broad; it includes all diffeomorphisms with hyperbolic nonwandering sets. Second, we study the so-called individual inverse shadowing (any exact trajectory can be traced by approximate ones, but this shadowing is not uniform with respect to the initial point of the trajectory). We demonstrate that this property is closely related to structural stability and Ω-stability of diffeomorphisms.
Investigating Analytics Dashboards’ Support for the Value-based Healthcare Delivery Model
- Mona Isazad Mashinchi
- Adegboyega Ojo
- J. Francis Sullivan
2020 Pełny tekst
Improving the value of care is one of the essential aspects of Value-Based Healthcare (VBHC) model today. VBHC is a new HC delivery model which is centered on patient health outcomes and improvements. There is anecdotal evidence that the use of decision aid tools like dashboards can play a significant role in the successful implementation of VBHC models. However, there has been little or no systematic studies and reviews to establish the extent to which analytics dashboards are used to support patient care in a VBHC delivery context. This paper bridges this knowledge gap through a systematic review of the existing literature on dashboards in the HC domain. Our study reveals dashboard capabilities as an enabling tool for value improvements and provides insight into the design of dashboards. This study concludes by highlighting a few gaps, question, and need for research in the future.
Investigating Feature Spaces for Isolated Word Recognition
- Povilas Treigys
- Grazina Korvel
- Gintautas Tamulevicius
- Jolita Bernataviciene
- Bożena Kostek
2020
The study addresses the issues related to the appropriateness of a two-dimensional representation of speech signal for speech recognition tasks based on deep learning techniques. The approach combines Convolutional Neural Networks (CNNs) and time-frequency signal representation converted to the investigated feature spaces. In particular, waveforms and fractal dimension features of the signal were chosen for the time domain, and three feature spaces were investigated for the frequency domain, namely: Linear Prediction Coefficient (LPC) spectrum, Hartley spectrum, and cochleagram. Due to the fact that deep learning requires an adequate training set size of the corpus and its content may significantly influence the outcome, thus for the data augmentation purpose, the created dataset was extended with mixes of the speech signal with noise with various SNRs (Signal-to-Noise Ratio). In order to evaluate the applicability of the implemented feature spaces for isolated word recognition task, three experiments were conducted, i.e., 10-, 70-, and 111-word cases were analyzed.
Investigating the Impact of Curing System on Structure-Property Relationship of Natural Rubber Modified with Brewery By-Product and Ground Tire Rubber
- Łukasz Zedler
- Xavier Colom
- Javier Cañavate
- Mohammad Saeb
- Józef Haponiuk
- Krzysztof Formela
2020 Pełny tekst Polymers
The application of wastes as a filler/reinforcement phase in polymers is a new strategy to modify the performance properties and reduce the price of biocomposites. The use of these fillers, coming from agricultural waste (cellulose/lignocellulose-based fillers) and waste rubbers, constitutes a method for the management of post-consumer waste. In this paper, highly-filled biocomposites based on natural rubber (NR) and ground tire rubber (GTR)/brewers’ spent grain (BSG) hybrid reinforcements, were prepared using two different curing systems: (i) sulfur-based and (ii) dicumyl peroxide (DCP). The influence of the amount of fillers (in 100/0, 50/50, and 0/100 ratios in parts per hundred of rubber) and type of curing system on the final properties of biocomposites was evaluated by the oscillating disc rheometer, Fourier-transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, swelling behavior, tensile testing, and impedance tube measurements. The results show, that the scorch time and the optimum curing time values of sulfur cured biocomposites are affected by the change of the hybrid filler ratio while using the DCP curing system, and the obtained values do not show significant variations. The results conclude that the biocomposites cured with sulfur have better physico-mechanical and acoustic absorption, and that the type of curing system does not influence their thermal stability. The overall analysis indicates that the difference in final properties of highly filled biocomposites cured with two different systems is mainly affected by the: (i) cross-linking efficiency, (ii) partial absorption and reactions between fillers and used additives, and (iii) affinity of additives to applied fillers.
Investigation into MPI All-Reduce Performance in a Distributed Cluster with Consideration of Imbalanced Process Arrival Patterns
- Jerzy Proficz
- Piotr Sumionka
- Jarosław Skomiał
- Marcin Semeniuk
- Karol Niedzielewski
- Maciej Walczak
2020 Pełny tekst Advances in Intelligent Systems and Computing
The paper presents an evaluation of all-reduce collective MPI algorithms for an environment based on a geographically-distributed compute cluster. The testbed was split into two sites: CI TASK in Gdansk University of Technology and ICM in University of Warsaw, located about 300 km from each other, both connected by a fast optical fiber Ethernet-based 100 Gbps network (900 km part of the PIONIER backbone). Each site hosted a set of 10~compute nodes interconnected locally by the InfiniBand switches with the traffic forwarded by specialized hardware: IBEX G40 - QDR InfiniBand RDMA based Extension Platform. A set of six all-reduce algorithms, consisting of two ring-based (including a PAP-aware pre-reduced ring), two binomial-tree based and two hierarchical ones, was tested for balanced and imbalanced process arrival patterns (PAPs). The results showed high and stable bandwidth with large data transmission latency of the branch connecting the remote sites (about 13 ms in comparison to 10 us locally), and for the tested algorithms there was an advantage of hierarchical approach, and then binomial tree. Finally, we also observed some performance increase in PAP-aware solution in comparison to its regular counterpart. The main conclusion is that for the distributed cluster environment with imbalanced PAPs, there is a need for designing new hierarchical algorithms with PAP-aware support.
Investigation of Parallel Data Processing Using Hybrid High Performance CPU + GPU Systems and CUDA Streams
- Paweł Czarnul
2020 Pełny tekst COMPUTING AND INFORMATICS
The paper investigates parallel data processing in a hybrid CPU+GPU(s) system using multiple CUDA streams for overlapping communication and computations. This is crucial for efficient processing of data, in particular incoming data stream processing that would naturally be forwarded using multiple CUDA streams to GPUs. Performance is evaluated for various compute time to host-device communication time ratios, numbers of CUDA streams, for various numbers of threads managing computations on GPUs. Tests also reveal benefits of using CUDA MPS for overlapping communication and computations when using multiple processes. Furthermore, using standard memory allocation on a GPU and Unified Memory versions are compared, the latter including programmer added prefetching. Performance of a hybrid CPU+GPU version as well as scaling across multiple GPUs are demonstrated showing good speed-ups of the approach. Finally, the performance per power consumption of selected configurations are presented for various numbers of streams and various relative performances of GPUs and CPUs.
Investigation of praseodymium and samarium co-doped ceria as an anode catalyst for DIR-SOFC fueled by biogas
- Beata Bochentyn
- Piotr Błaszczak
- Maria Gazda
- A. Fuerte
- S. F. Wang
- Piotr Jasiński
2020 Pełny tekst INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
The Pr and Sm co-doped ceria (with up to 20 mol.% of dopants) compounds were examined as catalytic layers on the surface of SOFC anode directly fed by biogas to increase a lifetime and the efficiency of commercially available DIR-SOFC without the usage of an external reformer. The XRD, SEM and EDX methods were used to investigate the structural properties and the composition of fabricated materials. Furthermore, the electrical properties of SOFCs with catalytic layers deposited on the Ni-YSZ anode were examined by a current density-time and current density-voltage dependence measurements in hydrogen (24h) and biogas (90h). Composition of the outlet gasses was in situ analysed by the FTIR-based unit. It has been found out that Ce0.9Sm0.1O2-δ and Ce0.8Pr0.05Sm0.15O2-δ catalytic layers show the highest stability over time and thus are the most attractive candidates as catalytic materials, in comparison with other investigated lanthanide-doped ceria, enhancing direct internal reforming of biogas in SOFCs.
Investigation of rotational state-changing collisions of C2N− ions with helium
- Jan Franz
- Francesco Antonio Gianturco
2020
The cross sections for rotational inelastic collisions between atoms and a molecular anion can be very large, if the anion has a dipole moment. This makes molecular anions very efficient in cooling atomic gases. We address rotational inelastic collisions of Helium atoms with the molecular anion C2N–. Here we present preliminary calculations of the potential energy surface.
Investigation of the Dynamism of Nanosized SOA Particle Formation in Indoor Air by a Scanning Mobility Particle Sizer and Proton-Transfer-Reaction Mass Spectrometry
- Klaudia Pytel
- Renata Marcinkowska
- Bożena Zabiegała
2020 Pełny tekst MOLECULES
Terpenes are VOCs of particular importance, since they are emitted from a wide range of indoor sources and are considered to be precursors of Secondary Organic Aerosol (SOA) formation. It has been proven that SOA particles, especially nanosized ones, pose a threat to human health. In this research, experiments with the application of an environmental chamber and real-time measurement techniques were carried out to investigate in a complimentary way the formation of monoterpene oxidation products and nanosized SOA particles initiated by monoterpene ozonolysis. Proton-Transfer-Reaction Mass Spectrometry with a Time-Of-Flight analyzer (PTR-TOF-MS) and a Scanning Mobility Particle Sizer (SMPS) were applied to determine in real time the dynamism of the formation of the corresponding terpene ozonolysis products and submicron SOA particles. Results proved that firstly, oxidation products were formed, and then, they underwent nucleation and condensation, forming particles whose diameters grew with time. The oxidation products formed were different depending on the type of terpenes applied. The comparison of the results obtained during the experiments with gaseous standard mixtures and real samples commonly present and used in indoor air revealed that the diversified chemical composition of the emission source had implications for both the particle formation initiated by the oxidation of essential oil components and the chemical reactions occurring via the oxidation process. With the instrumentation utilized, the concentration changes at the level of a few ppbv could be monitored
Investigation on the Sources and Impact of Trace Elements in the Annual Snowpack and the Firn in the Hansbreen (Southwest Spitsbergen)
- Andrea Spolaor
- Beatrice Moroni
- Bartłomiej Luks
- Adam Nawrot
- Marco Roman
- Catherine Larose
- Łukasz Stachnik
- Federica Bruschi
- Krystyna Kozioł
- Filip Pawlak
- Clara Turetta
- Elena Barbaro
- Jean-Charles Gallet
- David Cappelletti
2020 Pełny tekst Frontiers in Earth Science
We present a thorough evaluation of the water soluble fraction of the trace element composition (Ca, Sr, Mg, Na, K, Li, B, Rb, U, Ni, Co, As, Cs, Cd, Mo, Se, Eu, Ba, V, Ge, Ga, Cr, Cr, P, Ti, Mn, Zr, Ce, Zn, Fe, Gd, Y, Pb, Bi, Yb, Al, Nb, Er, Nd, Dy, Sm, Ho, Th, La, Lu, Tm, Pr, Tb, Fe, In, Tl) and their fluxes in the annual snowpack and the firn of the Hansbreen (a tidewater glacier terminating in the Hornsund fjord, southwest Spitsbergen). The trace element samples were obtained from a 3 m deep snow pit dug at the plateau of the glacier (450 m a.s.l.), and from a 2 m deep firn core collected from the bottom of the snow pit. The comparison of elemental fluxes and enrichment factors allowed us to constrain specific summer and wintertime deposition patterns of water soluble trace elements in the southern part of the Svalbard archipelago. Our results suggest that the chemical composition of the Hansbreen (and likely other glaciers where the summit is close to the equilibrium line) is mainly affected by summertime deposition of trace elements from local sources and some volatile elements, which may be transported into the Arctic when polar vortex is weak. The melting of the annual snowpack seems to have a minor influence on the overall chemical signature of the glacier ice.
Investigations of the Methods of Time Delay Measurement of Stochastic Signals Using Cross-correlation with the Hilbert Transform
- Robert Hanus
- Marcin Zych
- Rafał Chorzępa
- Anna Golijanek-Jędrzejczyk
2020 Pełny tekst
The article presents the results of simulation studies of four methods of estimating time delay for random signals using cross-correlation with the Hilbert Transform. Selected models of mutually delayed stochastic signals were used in the simulations, corresponding to the signals obtained from scintillation detectors in radioisotope measurements of liquid-gas two-phase flow. Standard deviations of the values of the individual functions were designated and compared, along with standard deviations of time delay estimates determined on their basis. The obtained results were compared with the results for classic cross-correlation function (CCF). It was found that for the analysed range of the signal-to-noise ratio (SNR): 0.2 ≤ SNR ≤ 5, the lowest values of standard deviation of time delay estimates were obtained for the CCFHT function (cross-correlation with the Hilbert Transform of the delayed signal).
Investigations of the Working Process in a Dual-Fuel Low-Emission Combustion Chamber for an FPSO Gas Turbine Engine
- Serhiy Serbin
- Badri Diasamidze
- Marek Dzida
2020 Pełny tekst Polish Maritime Research
This investigation is devoted to an analysis of the working process in a dual-fuel low-emission combustion chamber for a floating vessel’s gas turbine. The low-emission gas turbine combustion chamber with partial pre-mixing of fuel and air inside the outer and inner radial-axial swirlers was chosen as the object of research. When modelling processes in a dual-flow low-emission gas turbine combustion chamber, a generalized method is used, based on the numerical solution of the system of conservation and transport equations for a multi-component chemically reactive turbulent system, taking into consideration nitrogen oxides formation. The Eddy-Dissipation-Concept model, which incorporates Arrhenius chemical kinetics in a turbulent flame, and the Discrete Phase Model describing the interfacial interaction are used in the investigation. The obtained results confirmed the possibility of organizing efficient combustion of distillate liquid fuel in a low-emission gas turbine combustion chamber operating on the principle of partial preliminary formation of a fuel-air mixture. Comparison of four methods of liquid fuel supply to the channels of radial-axial swirlers (centrifugal, axial, combined, and radial) revealed the advantages of the radial supply method, which are manifested in a decrease in the overall temperature field non-uniformity at the outlet and a decrease in nitrogen oxides emissions. The calculated concentrations of nitrogen oxides and carbon monoxide at the flame tube outlet for the radial method of fuel supply are 32 and 9.1 ppm, respectively. The results can be useful for further modification and improvement of the characteristics of dual-fuel gas turbine combustion chambers operating with both gaseous and liquid fuels.
Ion recognition properties of new pyridine-2,6-dicarboxamide bearing propeller-like pendant residues: multi-spectroscopic approach
- Ewa Wagner-Wysiecka
- Natalia Łukasik
- Andrzej Okuniewski
- Błażej Galiński
2020 Pełny tekst MONATSHEFTE FUR CHEMIE
The synthesis and ion binding properties of new amide derived from propeller-like tris(2-pyridyl)amine and 2,6-pyridinedicarboxylic acid chloride were described. Amide binds divalent metal cations: copper(II), nickel(II), zinc(II), and lead(II) in acetonitrile. In acetonitrile:water mixture (9:1 v/v) amide interacts only with copper(II) and nickel(II) cations forming complexes of 1:1 stoichiometry. It was found that the introduction of bulky, nitrogen donor atom bearing pendant groups can influence coordination mode of pyridine-2,6-dicarboxamides. The probable model of ligand-ion interactions is proposed on the basis of 1H NMR and FT-IR spectroscopy.
Ionic liquids in the microextraction techniques: the influence of ILs structure and properties
- Kateryna Yavir
- Karolina Konieczna
- Łukasz Marcinkowski
- Adam Kloskowski
2020 TRAC-TRENDS IN ANALYTICAL CHEMISTRY
Ionic liquids (ILs) are composed entirely of ions thus they possess unique properties, including negligible volatility, a liquid state in a broad range of temperatures and ability to change them depending on the chosen type of anion and cation, which make ILs unique and useful for many applications in sample preparation techniques. A deeper understanding of the nature of ILs and the impact of their structure on their parameters is the key to the success of conscious use of them as potential sorption media for a given purpose. This review describes the key physical and chemical properties of ILs in the context of their importance in sample preparation techniques. The review also presents selected combinations of ILs with solid-phase microextraction, SPME; single drop microextraction, SDME; dispersive liquid-liquid microextraction, DLLME, in terms of the role of ILs properties in a given technique.
Iron doped manganese cobaltite spinel coatings produced by electrophoretic co-deposition on interconnects for solid oxide cells: Microstructural and electrical characterization
- Elisa Zanchi
- Sebastian Molin
- A Sabato
- B Talic
- Grzegorz Cempura
- A Boccaccini
- F Smeacetto
2020 JOURNAL OF POWER SOURCES
We report a systematic microstructural and electrical characterization of iron doped Mn–Co spinel coatings processed by electrophoretic co-deposition of Mn1.5Co1.5O4 and Fe2O3 powders on Crofer 22 APU and AISI 441 steel substrates. Iron addition to Mn–Co spinel coating leads to a reduction of the area specific resistance on both substrates, after 3200 h at 750 °C. The Fe doped Mn–Co coating both leads to a thinner oxide scale and reduces the sub scale oxidation for the Crofer 22 APU substrate. Fe doped Mn–Co on AISI 441 shows both a thicker oxide scale and low area specific resistance values, likely due to a doping effect of the oxide scale by minor alloying elements. The different mechanisms by which iron doping of Mn–Co spinels can influence elemental interdiffusion at the steel-oxide scale-coating interfaces and relative contributions to the overall area specific resistance are evaluated by means of advanced electron microscopy. The promising results are further confirmed in a cell test, where the Fe doped MnCo coated interconnect does not induce any degradation of the oxygen electrode, proving its efficiency.
Is Artificial Intelligence Ready to Assess an Enterprise’s Financial Security?
- Oleksandr Melnychenko
2020 Pełny tekst Journal of Risk and Financial Management
This study contributes to the literature on financial security by highlighting the relevance of the perceptions and resulting professional judgment of stakeholders. Assessing a company’s financial security using only economic indicators—as suggested in the existing literature—would be inaccurate when undertaking a comprehensive study of financial security. Specifically, indices and indicators based on financial or managerial reporting calculated at any particular point in time, provide only a superficial understanding—and may even distort the overall picture. It has also been suggested that expert assessment is the most objective method, although it has disadvantages related to individual cognitive limitations. These limitations are not particular to artificial intelligence, which could assess an enterprise’s financial security in a less biased way. However, by only imitating human behavior, it is not able to perceive and evaluate with intuition the dynamics of the company’s development and holistically assess the financial condition—despite the possibility of learning and forecasting—because artificial intelligence is not able to think and predict, which, in an enterprise, is the most important skill of a manager. Therefore, the risk of developing artificial intelligence to assess a firm’s financial security lies in a biased assessment of the enterprise’s activities in general—and its financial security in particular.