2019 - Repozytorium publikacji - Politechnika Gdańska

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Publikacje z roku 2019

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Rzadka reprezentacja sygnału niestacjonarnego w technice oszczędnego próbkowania
- Beata Pałczyńska
- Dariusz Świsulski
2019 Pełny tekst Przegląd Elektrotechniczny
Przedstawiono zastosowanie techniki oszczędnego próbkowania do rekonstrukcji sygnału niestacjonarnego na podstawie skompresowanych próbek w dziedzinie czas-częstotliwość. Zastosowano nadmiarowy algorytm z różnymi słownikami aby znaleźć rzadką reprezentację sygnału. Wyniki symulacji potwierdzają, że zastosowanie oszczędnego próbkowania pozwala na rekonstrukcję sygnału niestacjonarnego z małej liczby losowo pobranych próbek, z niewielką utratą jakości rekonstrukcji.
Safety assessment of a concrete viaduct damaged by vehicle impact and an evaluation of the repair
- Mikołaj Miśkiewicz
- Dawid Bruski
- Jacek Chróścielewski
- Krzysztof Wilde
2019 Pełny tekst ENGINEERING FAILURE ANALYSIS
Damage to lower parts of viaducts caused by impact from under-passing high vehicles is relatively frequent. One such incident, in which a viaduct was damaged by the impact from a truck with an improperly assembled hydraulic crane, is considered in this work. The analysis is based on a detailed object damage evaluation, 3D laser scanning, and numerical simulations. The aim of the study is to accurately model the vehicle impact into the viaduct's span. The objective is to diagnose internal damage and to assess the proposed repair concept. No other method will allow discovery of the internal damage, including whether the pre-stressing tendons have been damaged or not. The computational model considers non-linear system dynamics including advanced material definition and the technology of tendon pre-stressing. All complex stages of structural assembly are included in the simulations and the extent of bridge damage is diagnosed. This approach makes it possible to reliably restore the collision event and to assess the safety of internal structural parts. The results from the numerical simulation correspond to the damage measured on the full-scale object. The conducted research indicates that tendons were not damaged as a result of vehicle impact. The structure may be strengthened by means of assembling prestressed concrete girders at both ends. This restoring concept is confirmed analytically. The strengthened structure is intended to show an even greater safety reserve. The proposed strengthening substantially improved structural stiffness, significantly reducing concrete damage and tendon stress in the case of a similar impact in the future. The proposed methodology can also help with research and in practice to assess the safety of other similarly struck and damaged bridges.
Safety Assessment of Tram Stops
- Agnieszka Tubis
- Mateusz Rydlewski
- Marcin Budzyński
2019 Pełny tekst Journal of KONBiN
The safety of public transport stops is the subject of numerous studies in large agglomerations around the world. This is due to the fact that it is a passenger exchange zone where collisions and accidents involving people getting on or off public transport vehicles most often occur. For this reason, the purpose of the article is to present the results of the safety assessment of the stop zones for two selected tram lines in Wroclaw. The assessment of tram stops is based on an indicator that takes into account three parameters that affect the safety level of the tram stop zone - the location and infrastructure of the tram stop, its availability and traffic in the tram stop zone. The analysis of stops has been prepared on the basis of direct observation. As a result of the assessment process, these stops were indicated, whose safety index was the lowest. The improvement solutions for them should be prepared at first.
Sanctions and their role in preventing the appropriation of the creditor’s property rights in bankruptcy proceedings–the case of Poland
- Sylwia Morawska
- Błażej Prusak
- Przemysław Banasik
- Woźniak-jęchorek Beata
2019 Pełny tekst Economics and Business Review
The aim of this paper is to fill the cognitive gap regarding the role of sanc-tions in the protection of a creditor’s property rights in the event of an entrepreneur insolvency. The impact of sanctions on transaction costs, including their identifica-tion and types, as well as the impact on the protection of creditor rights, has been poorly recognized in the subject literature to date. This article investigates the theory of transaction costs and property rights by providing an identification and description of formal negative sanctions, as well as their impact on counteracting the appropria-tion of creditors’ rights in bankruptcy proceedings. These studies are part of the dis-cussion on the role of formalized negative sanctions, in terms of enforcing behaviours expected by the legislator.
Scattering and Propagation Analysis for the Multilayered Structures Based on Field Matching Technique
- Małgorzata Warecka
- Rafał Lech
- Piotr Kowalczyk
2019 Pełny tekst
A semi-analytical method is employed to the analysis of scattering and guiding problems in multilayer dielectric structures. The approach allows to investigate objects with arbitrary convex cross section and is based on the direct field matching technique involving the usage of the field projection at the boundary on a fixed set of orthogonal basis functions. For the scattering problems the scattered field in the far zone is calculated and for the guiding problems a complex root finding algorithm is utilized to determine the propagation coefficients. The results are compared with the alternative solutions in order to verify the validity of the proposed method.
Scenarios in the development strategies of larger cities in Poland
- Jacek Sołtys
2019 Pełny tekst PRACE NAUKOWE UNIWERSYTETU EKONOMICZNEGO WE WROCŁAWIU
Summary: Planning prepares decisions and future actions. Therefore, future conditions should be considered in planning, in particular strategic planning, due to its long-term nature. To accomplish this, certain prognostic methods should be applied. A scenario method is seen as one of the most useful prognostic method, especially in cases when social and institutional behaviour plays a crucial role. The aim of the paper is an analysis and evaluation of the application of scenarios in the development strategies of larger cities in Poland (more than 100 thousand inhabitants). Scenarios were prepared in 13 out of the 39 cities. All these scenarios were analyzed. The scenarios were formulated with the intuitive logics method. Most scenarios do not fully meet the scenario definition because of the insufficiency of the sequences of events presented on the timeline. The author discusses some methodological problems concerning the creation of scenarios and the problems in using scenarios, and gives some recommendations.
Scoreboard Architectural Pattern and Integration of Emotion Recognition Results
- Agnieszka Landowska
- Grzegorz Brodny
2019 Pełny tekst IEEE Access
This paper proposes a new design pattern, named Scoreboard , dedicated for applications solving complex, multi-stage, non-deterministic problems. The pattern provides a computational framework for the design and implementation of systems that integrate a large number of diverse specialized modules that may vary in accuracy, solution level, and modality. The Scoreboard is an extension of Blackboard design pattern and comes under behavioral type. The pattern allows for an integration of multimodal results, employing early, and/or late fusion paradigms. Additionally, it provides a framework for the evaluation of the modules, dealing with inconsistency and low accuracy. In this paper, the Scoreboard design pattern is described with the standard meta-data model, followed by a sample implementation. This paper also provides the evaluation results based on experiments and a case study. The evaluation results confirmed the robustness, modularization, ease of integration, efficiency, and adaptability of the solutions with the Scoreboard pattern in comparison with the Blackboard pattern and ‘‘no pattern’’ condition. This paper provides also a case study of Scoreboard application in an integration of emotion recognition results. There are certain complex problems in modern software engineering which require multi-stage, multi-party, multi-modal solutions, and non-deterministic control strategies. Among those are natural language processing, image processing, and emotion recognition, to name just a few. The proposed Scoreboard pattern might be used in the software addressing the problems, especially in research systems that explore large solution spaces and require runtime decisions on execution order.
Sealing tax collection in Poland and the EU in the years 2008–2018
- Wojciech Wyrzykowski
- Piotr Kasprzak
2019 Pełny tekst Zeszyty Naukowe Małopolskiej Wyższej Szkoły Ekonomicznej w Tarnowie
The purpose of this study is to present issues related to sealing tax collection system in Poland and European Union countries as well as OECD members in 2008–2018. The article is divided into four parts, which include: introduction, origin of the problem, implemented solutions and conclusions. It presents the results of the conducted analysis including studies of the literature and empirical data (mainly from OECD, GUS—Polish Central Statistical Office and Eurostat sources as well as professional industry reports) as well as the structure of the tax systems in Europe. The following result is a presentation of the origin of the problem, i.e. the occurrence of revenue decrease in tax collection after 2008, and actions that were undertaken to reduce the effects of this negative phenomenon. The authors also present a preliminary assessment of the actions conducted by particular countries along with their level of effectiveness in achieving the goals, which was to reduce the level of tax frauds.
Searching by Heterogeneous Agents
- Dariusz Dereniowski
- Łukasz Kuszner
- Robert Ostrowski
2019
In this work we introduce and study a pursuit-evasion game in which the search is performed by heterogeneous entities. We incorporate heterogeneity into the classical edge search problem by considering edge-labeled graphs. In such setting a searcher, once a search strategy initially decides on the label of the searcher, can be present on an edge only if the label of the searcher and the label of the edge are the same. We prove that such searching problem is not monotone even for trees and moreover we give instances in which the number of recontamination events is Ω(n^2), where n is the size of a tree. Another negative result regards the NP-completeness of the monotone heterogeneous search in trees. The two above properties show that this problem behaves very differently from the classical edge search. On the other hand, if all edges of a particular label form a (connected) subtree of the input tree, then we show that optimal heterogeneous search strategy can be computed efficiently.
Seasonal changes of the concentrations of mineral forms of nitrogen and phosphorus in watercourses in the agricultural catchment area (Bay of Puck, Baltic Sea, Poland)
- Ewa Wojciechowska
- Nicole Nawrot
- Karolina Matej-Łukowicz
- Magdalena Gajewska
- Hanna Obarska-Pempkowiak
2019 Pełny tekst Water Science and Technology-Water Supply
The Baltic Region countries are obliged to meet the stringent limits of N and P discharge set by HELCOM for 2021. Area sources of pollution, including agriculture, are considered the main contributors of biogenic compounds. The Bay of Puck as an inner part of the Baltic Sea is particularly sensitive to eutrophication caused by nutrient in flow from agricultural lands. Rivers and streams inflowing to the Bay of Puck transport nitrogen and phosphorus compounds washed out from fields. The article discusses concentrations of nitrogen and phosphorus compounds measured during annual research (VII.2017–VI.2018) at three watercourses: Płutnica, Reda and Bładzikowski Stream inflowing to the Bay of Puck. The concentrations ranged from 0.01 to 0.13 mg/L N-NO2, from 0.39 to 7.55 mg/L N-NO3, from 0.03 to 0.58 mg/L N-NH4, from 0.44 to 9.51 mg/L TN, from 0.05 to 0.45 mg/L P-PO4 and from 0.03 to 1.89 mg/L TP. Seasonal changes of nutrient concentrations were observed, with maximum concentrations of nitrates in August and September after application of fertilizers to arable land.
Secure Quaternion Feistel Cipher for DICOM Images
- Mariusz Dzwonkowski
- Roman Rykaczewski
2019 IEEE TRANSACTIONS ON IMAGE PROCESSING
An improved and extended version of a quaternion-based lossless encryption technique for digital image and communication on medicine (DICOM) images is proposed. We highlight and address several security flaws present in the previous version of the algorithm originally proposed by Dzwonkowski et al. (2015). The newly proposed secure quater- nion Feistel cipher (S-QFC) algorithm retains the concept of a modified Feistel network with modular arithmetic and the use of special properties of quaternions to perform rotations of data sequences in 3D space for each of the cipher rounds. A new and more secure key generation scheme based on quaternion Julia sets is utilized. We also introduce both-sided modular matrix multiplications for the encryption and decryption processes. The proposed S-QFC algorithm eliminates the major security flaws of its predecessor while maintaining high computation speed in comparison to other algorithms originally embedded in DICOM (i.e., advanced encryption standard and triple data encryption standard). A computer-based analysis has been carried out. Simulation results and cryptanalysis are shown at the end of this paper.
Security-oriented agile approach with AgileSafe and OWASP ASVS
- Katarzyna Łukasiewicz
- Sara Cygańska
2019
In this paper we demonstrate a security enhancing approach based on a method called AgileSafe that can be adapted to support the introduction of OWASP ASVS compliant practices focused on improving security level to the agile software development process. We also present results of the survey evaluating selected agile inspired security practices that can be incorporated into an agile process. Based on the survey’s results, these practices were used as an input to AgileSafe method as well as to demonstrate their potential to comply with OWASP ASVS requirements.
Seismic pounding between adjacent buildings: Identification of parameters, soil interaction issues and mitigation measures
- Mahmoud Miari
- Kok Choong
- Robert Jankowski
2019 SOIL DYNAMICS AND EARTHQUAKE ENGINEERING
Structural pounding has been observed in many previous earthquakes due to insufficient gap commonly provided between adjacent structures. The collisions usually generate large impact forces and short duration acceleration pulses which may result in significant damage to the colliding buildings. Because of that, earthquake induced structural pounding has been intensively studied and investigated for the last three decades. Results of some of these investigations are compatible, whereas others contradict. This work reviews previous research studies concerning earthquake-induced structural pounding aiming to better understand pounding phenomenon itself and the reasons behind the contradictory results. The effect of pounding on buildings with fixed bases, isolated buildings, and buildings resting on soft soils are discussed. Then, aspects of a sufficient recommended gap are considered. Appropriate mitigation measures are also addressed and directions of the future research studies on structural pounding are recommended.
Seismic Response of High-Rise Buildings Equipped with Base Isolation and Non-Traditional Tuned Mass Dampers
- Hosein Naderpour
- Naghmeh Naji
- Daniel Burkacki
- Robert Jankowski
2019 Pełny tekst Applied Sciences-Basel
One of the methods in structural control is the application of combinational control systems in order to reduce the response of structures during earthquakes. The aim of the present paper is to verify the effectiveness of a hybrid control strategy, combining base isolation and non-traditional tuned mass dampers (TMDs) (i.e., TMDs with dashpots directly connected to the ground) in suppressing structural vibrations of high-rise buildings. The study was conducted for structures with a different number of stories exposed to various far-field and near-field earthquake records. Multi degree-of-freedom models of buildings as well as non-linear models of the base isolation system were employed in the analysis. The results of the study clearly confirmed that the response of high-rise buildings during earthquakes could be significantly reduced using base isolation devices and non-traditional TMDs. They showed also that the effectiveness in suppressing structural vibrations substantially depends on the type of the control system used. The influence of the base isolation in the reduction of structural response under different earthquake records was much larger than the influence of non-traditional TMDs. In the case of buildings analyzed in the study, the application of TMDs alone resulted in a reduction not larger than 20%, as compared to the response without any system. On the other hand, the response of buildings equipped with only base isolation devices was reduced by more than 70% under different ground motions. However, the largest reductions (larger than 80%) were obtained for the cases when both control systems (base isolation and non-traditional TMDs) were used simultaneously.
Selected Aspect of IT Tools Application in Process Improvement in Industrial Laundry Services
- Piotr Grudowski
- Mateusz Muchlado
2019 Advances in Intelligent Systems and Computing
The laundry services sector in Poland is growing dynamically and currently has around 13,000 enterprises, mainly micro, small and medium size. The increasing competitiveness of this industry, causes more emphasis on solutions that can in-crease the efficiency of laundry processes and thereby strengthen the market position. One of the methods that can be used for this purpose is Lean Six Sigma, aided by specialized computer software. The paper describes the process of professional washing of work clothes, analyze of its losses and according to that presents the implementation of IT solutions to support the implementation of LSS objectives. The main purpose of this article is to present the lean concept based identification of selected sources of losses in the key operational process of the company providing laundry services and to determine the possibilities of their reduction through the use of appropriate IT tools. This paper contains an analysis of the case study in which this system was applied.
Selected Aspects of Biofuels Market and the Electromobility Development in Poland: Current Trends and Forecasting Changes
- Adam Kupczyk
- Joanna Mączyńska
- Grzegorz Redlarski
- Karol Tucki
- Anna Bączyk
- Dominik Rutkowski
2019 Pełny tekst Applied Sciences-Basel
This work presents basic information associated with markets of selected alternative fuels used in transport, such as methyl esters, conventional bioethanol and lignocellulosic bioethanol, and the market of electrical vehicles. Legal conditions, which stimulate development and regulate the mode of functioning of the liquid biofuel market until 2020 are discussed, based on provisions of EU directives. Data on biofuel production in Poland are presented, as well as biofuel consumption in the EU, the USA and Brazil in 2017. The most important conclusions of the proposal for a directive on the promotion of renewable energy sources in transport in EU member states in years 2021–2030 are discussed. The authors have also indicated the key legal and territorial conditions associated with the development of electromobility and present basic information on electric vehicles in Poland and Europe. The results of the research on the attractiveness of these sectors in 2018 are presented and compared with the results obtained in years 2007–2017. A score-based sector attractiveness method was used in the research.
Selected Issues of Hybrid Outboard Motors
- Wojciech Leśniewski
2019 Pełny tekst Polish Maritime Research
The aim of the research reported in the article was designing a hybrid drive system based on an outboard internal combustion engine offered by a selected producer and testing its operating characteristics. The article presents different designs of this type of drive which can be found in the literature and are available in the market. The designed hybrid outboard drive system was tested both on the laboratory test rig and in real operating conditions. The results of these tests are included.
Selected Problems of Experimental Testing Marine Stern Tube Bearings
- Agnieszka Barszczewska
- Ewa Piątkowska
- Wojciech Litwin
2019 Pełny tekst Polish Maritime Research
This paper presents typical methods for conducting experimental tests on main shaft slide bearings. There are described their possible testing capabilities, advantages, drawbacks and limitations. Various testing methods were analyzed to find a solution able of providing a wide range of possible investigations at possibly acceptable limitations.
Selected properties and parameters of radio channel impulse response estimation in ISM 2.4 GHz band
- Agnieszka Czapiewska
- Ryszard Studanski,
2019 Proceedings of SPIE
The article presents experimental research indicating that the impulse response of the communication channel, determined in practice, are not of an universal character, but only represent its approximate value for the frequency on which this measurement was made. Phases for each of the replicas of the measurement signal were determined during the analysis of the received signals in the baseband. Phase changes of individual replicas of the signal as a function of changes in the position of one of the measuring antennas are presented. The coherence bandwidth and the coherence time of the channel were determined. The tests were carried out in urban environment in static conditions and when antennas were moving
Selected Stability Problems of Thin-Walled Columns and Beams
- Czesław Szymczak
- Marcin Kujawa
2019
The article reviews a number of papers in the light of buckling analy- sis of thin-walled columns and beams. Stability of thin-walled columns and beams are considered a vital engineering science issue in both historical and present-day approaches. The paper refers to the recent authors’ works of the 2012–2019 period, published in leading journals. Similar review of stability problems of thin-walled structures developed at Gdansk University of Technology is published in Szymczak (A review of stability problems of thin-walled structures developed at Gdansk Uni- versity of Technology, 69–78, 2003, [58]), Szymczak (Selected problems of stability of thin-walled columns with bisymmetric cross-section, 111–128, 2012, [59]). This paper is a continuation of the earlier reviews. Only selected references are given.