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Gdańsk University of Technology

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Publications from the year 2017

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  • Research on entrepreneurship – the forms of entrepreneurship
    • Julita Wasilczuk
    2017 Full text Studia i Materiały Wydział Zarządzania Uniwersytet Warszawski

    The aim of this article is to present suggestions for future directions of research on entrepreneurship, with particular emphasis on different forms of entrepreneurship. The suggestions are preceded by a brief review of research on entrepreneurship. The article is theoretical in nature and does not present any own research, although its content is based on multiple years of experience in studying this phenomenon. The forms of entrepreneurship are discussed in terms of relationship with business, the methods of organization, the ownership of capital, the effect of entrepreneurial activities, phases of entrepreneurial activities and persons conducting business. The need to consider forms of entrepreneurship during research in such topic areas as governance methods and strategy selection, entrepreneurial motivation, innovations or the effects of entrepreneurial activity was pointed out.

  • Research on water lubricated main shaft bearings in conditions of improper lubrication and cooling conducted on high torque real-life scale bush test rig
    • Agnieszka Barszczewska
    • Wojciech Litwin
    • Jacek Sadowski
    2017

    Water lubricated polymer bushes find increasingly popular use in the sliding bearings of marine propellers, water turbines and pump shafts. Such popularity is partly due to their simple construction which also means relatively affordable price. In addition, properly designed and installed water lubricated bearings may well last for over a decade. However, in practical experience one may also observe cases of rapid wear or malfunction of this bearing type, some of which may be caused by insufficient flow of lubricant leading to overheating, especially in the bush material. The conducted research determined that certain bearings continue to work properly despite the absence of lubricant flow resulting in lack of constant cooling. This is due to low motion resistance levels resulting from low friction. The co-heat generated in the friction zone of such bearings is sufficiently low to be dispersed into surroundings once bearing's temperature rises and stabilizes at a safe level. The paper presents results of recent tests. The new test rig was built and first tests were conducted. The test rig makes it possible to investigate real scale bearings with shaft diameter of 100 mm and at high power propulsion (120kW). Thanks to this, the simulated conditions resemble those present on a small ship or hydropower unit where the transmitted power is high enough to destroy the bearing completely with melted polymer bush flowing out from the housing.

  • Reshaping of Coastlines as the Beginning of Urban Structures Changes in North Poland
    • Izabela Burda
    • Lucyna Nyka
    • Adam Borodziuk
    2017 Full text IOP Conference Series: Materials Science and Engineering

    This article discusses the problem of strategies concerning the processes of re-shaping the Baltic Sea southern coastline applied recently in North Poland. The undertaken research is an attempt to identify the relationship between the modifications of coastline forms and the positive changes of urban structures. It can be seen that these modifications are needed because of the problems of existing shoreline erosion. It can be also observed, that many realized interventions were helpful to save the land but they did not improve the condition of cities situated along the coast. In these cases it is impossible to connect the sea coastline with the existing grid of public spaces which is a barrier to creating a system that could be perceived as a coherent landscape. The basis for proving the importance of special ways of shoreline modifications are comparative studies and in-field analyses. In facing the problems of coastal cities there is a need to analyse the condition of existing urban structures. Worth noting is the fact that these structures have a unique character because of their location. They play an important role as holiday resorts being an attraction for many inhabitants and visitors from all over the world. Such a role plays, for example, an important part in places such as Jarosławiec, Ustka or Kołobrzeg. However, analysing the strategies applied in recent years, it can be noted that they cannot be the only basis for the strengthening of connections between land and water helping to preserve the land, but they may also play an important role as a factor for initiating urban structures transformations. What is also important, it can be claimed that relationships between sea water and urban structures should be strengthened due to special forms of the coast line. They should be integrated into existing structures making them more comfortable and attractive while also protecting against threats from the water. Playing the role as a protector of land they should use special constructions being at the same time accessible to all users throughout the year and regardless of weather conditions. It is worth emphasizing that special treatment of the coastline helps to establish it as a public domain which is important in achieving high quality urban-water landscapes. Therefore it should be the objective of strategies which are being prepared for parts of coastlines waiting for intervention.

  • (Re)Shaping Open Access Policy to Scientific Resources at Polish Technical Universities: Gdańsk University of Technology Perspective
    • Anna Wałek
    2017 Full text

    Developing European Open Access policy to scientific resources is one of the most important issues undertaken during the public debate about future scholarly communication trends. The Open Access landscape is determined by several factors (e.g. mandates). The open mandate: voluntary or mandatory, can be implemented at the institutional, national or international level. It requires scholars to use open repository to deposit results of scientific research funded with public money and research grants. The current paper reflects European Commission guidelines regarding disseminating scientific results funded with EU funds and recommendations at the national level for Polish universities. The process of preparing and implementing Open Access policy at the institutional level, and the role of libraries in this process were presented on the example of Gdańsk University of Technology in comparison to the other technical universities in Poland. Gdańsk University of Technology implements a project called Multidisciplinary Open System Transferring Knowledge. The acronym of its name in the Polish language is „MOST Wiedzy”, which means „the bridge of knowledge”. The repository is a project of an archive of scientific publications, scientific documentation, research data, scientific dissertations, as well as other documents and sources, created as a result of scientific experiments and other research and development work conducted at the Gdańsk University of Technology. It will also be a solution supporting communication between researchers and a platform for cooperation between science and business.

  • Resonance problems in UHV transmission lines
    • Jacek Klucznik
    • Zbigniew Lubośny
    • Krzysztof Dobrzyński
    • Stanisław Czapp
    2017

    The paper presents resonance phenomena observed in 400 kV transmission lines in the Polish power system. Two events are analysed, when shunt reactors used for reactive power compensation, caused overvoltages and overcurrent protection tripping as a result of resonance. An oscillographic fault recordings from protection devices are compared to time domain simulation results. The obtained simulation results match fault recordings, which allows the cause of the observed disturbances to be explained. The paper indicates resonance risks which should be avoided to ensure safe power system operation.

  • Restricted open shop scheduling
    • Michał Małafiejski
    • Krzysztof Pastuszak
    2017 Journal of Theoretical and Applied Computer Science

    In the real applications the open shop scheduling models often require some additional constraints and adequate models. We concern the restrictions in the open shop scheduling related to an instance of the problem and to a feasible solution. Precisely, we require that each jobs consists of the bounded number of operations and each machine has a bounded load (i.e., the total number of operations executed on this machine in a schedule). Moreover, in any feasible schedule we require some predetermined delays between the subsequent operations of the same job (no delays in the no-wait restriction) and each machine is working without any idle time (no-idle restriction). Although the open shop scheduling problem is NP-hard in general, we show some polynomial time algorithms using chromatic scheduling models for the selected open shop scheduling problems.

  • REVERSE MODELLING OF MICROSEISMIC WAVES PROPAGATION FOR THE INTERPRETATION OF THE DATA FROM HYDRAULIC FRACTURING MONITORING IN POLAND
    • Michał Antoszkiewicz
    • Mateusz Kmieć
    • Marek Szkodo
    • Robert Jankowski
    2017

    A hydraulic fracturing job was performed to stimulate gas flow from a horizontal wellbore located in Poland. The whole operation was overseen by means of microseismic monitoring. For this purpose, an array of 12000 geophones was deployed on ground in form of patches distributed unevenly in a region of 4km from the wellbore. The array was constantly recording seismic signals during whole fracturing processed. Such recorded signals can by analyzed to locate, both in time and space, events connected to cracking rocks. The information on rock cracks gives great insight into rock structure and process progress, which can facilitate more efficient resource usage and better overall fracturing results. Unfortunately, the rock formations overlaying reservoir rock strongly attenuate signal to a level that it is indistinguishable from background noise. Therefore, there is a need for a specialized algorithms that utilize coherence of signals that are related to real seismic events. One of such methods is reverse time modelling. Basing on a ground velocity model, one can simulate recorded wave propagation backwards in time. With this approach a wavefield focuses at the hypocenter of the recorded event. In our research modeling of wave propagation back in time was applied to seismic data acquired during hydraulic fracturing in Poland.

  • Review of ship safety domains: Models and applications
    • Rafał Szłapczyński
    • Joanna Szłapczyńska
    2017 OCEAN ENGINEERING

    Ship safety domain is a term which is widely used in research on collision avoidance and traffic engineering among others. Classic ship domains have been compared in multiple reports. However, up till now there has been no work summing up contemporary research in this field. The paper offers a systematic and critical review of the newer ship domain models and related research. It discusses multiple differences in approach to ship domain concept: from definitions and safety criteria, through research methodologies and factors taken into account, to sometimes largely different results obtained by various authors. The paper also points out some interpretation ambiguities related to ship domain and sums up present trends of its development and applications.

  • REVIEW ON COMPETITION АОB AND NОВ AS AN IMPORTANT ELEMENT FOR COST EFFECTIVE METHODS OF REMOVING NITROGEN FROM WASTEWATER
    • Jakub Drewnowski
    2017

    The aim of this paper is analysis of process principles and possible factors used to induce inhibition of nitrite oxidation by NOB (Nitrite Oxidizing Bacteria) which could be obtained during not very well understood processes: so called “shortcut” or “partial” nitrification as well deammonification, by qualitative/quantitative studies of AOB (Ammonium Oxidizing Bacteria) and NOB populations in activated sludge in dependency on chosen technological parameters (activated sludge concentration, share of AOB/NOB in biomass developed as act ivated sludge, DO set point control, intermittent aeration, temperature, pH, SRT strategy). The paper present a review on competition AOB and NOB as an important element for cost effective methods of removing nitrogen from wastewater.

  • Review on the quality of sediments from the stormwater drainage system in the urban area
    • Nicole Nawrot
    • Ewa Wojciechowska
    2017 Full text

    The main task of the stormwater drainage system is a safe drainage of rainwater and snowmelt from the urban area to the receiver. The flow of rain water in the drainage pipes is directly related with the formation of sediments in the whole stormwater system. In addition, pollutants from land runoff get adsorbed to the sediments. The sludge is mainly formed in those elements of stormwater drainage system, wherein the flow conditions allow for sedimentation – storm inlets, sedimentation tanks, separators and retention tanks. This article provides an overview of the literature concerning the characteristics of sediments from stormwater drainage system, with a particular focus on heavy metals in sediments deposited in the urban catchment area.

  • Revising Entrepreneurial Orientation Construct in Social Enterprise
    • Marzena Starnawska
    2017 Full text

    Entrepreneurial behavior and entrepreneurial orientation (EO) have received significant scholarly attention in entrepreneurship and management research, but mainly in the commercial context. However, some attempts discussing such behavior and EO among non-profit organizations, but limited in the social enterprise context. The literature argues that EO is higher in such contexts (Zahra, Gedajlovic, Neubaum & Shulman, 2009; Lumpkin, Moss, Grass, Kato & Amezcua, 2013). Also, some new EO dimensions are proposed, at the same time existing EO dimensions are redefined. Based on this limited literature, the author undertakes an overview of existing work on EO dimensions and analyses how EO can be reconstructed and redefined in the social enterprise context. New, additional EO dimensions are compiled and discussed: cooperation capacity, agility, and persistence. In the light of anecdotal, empirical efforts on EO construct and relationship to performance among social enterprises, it seems that EO needs more revision and theoretical discussion, combined with inductive and qualitative studies. This change can provide more insights into the nature of individual dimensions and their relevance for social and business performance of social enterprises. It also poses the question whether EO dimensions should go beyond the split between what is commercial and social in social enterprises, and encompass both or whether focus separately on each of the two.

  • REVISING ENTREPRENEURIAL ORIENTATION (EO) IN SOCIAL ENTREPRENEURSHIP, QUALITATIVE EVIDENCE FROM WORK INTEGRATION SOCIAL ENTERPRISES (WISES) FROM POLAND
    • Marzena Starnawska
    2017

    Entrepreneurial behaviour and entrepreneurial orientation (EO) of (commercial) entrepreneurship. have received significant scholarly attention in entrepreneurship and management research However, there are insufficient attempts discussing such behaviour and EO in non-profit, and particularly social entrepreneurship context, arguing that EO is higher in such contexts, or remains the same, some new EO dimensions are proposed, existing EO dimensions revised and redefined. In this study we ask how EO can be reconstructed and redefined in social entrepreneurship, especially in the area of work and social integration. Using exploratory, multiple-case, approach, based on purposive sample of 4 work and social integration enterprises (WISEs) as non-profit limited companies, we provide insights and suggestions for entrepreneurial orientation dimensions. We deliver a number of theoretical propositions on: performance, revise and discuss EO dimensions such as proactivity and innovativeness, risk taking, autonomy, but also propose new EO dimensions such as cooperation, performance of multiple roles.

  • Rewitalizacja małych i średnich miast
    • Katarzyna Russek
    2017 Full text Przestrzeń Ekonomia Społeczeństwo

    Małe i średnie miasta Polski borykają się dziś z wieloma problemami zarówno społecznymi, gospodarczymi jak i przestrzennymi. Mają one większe trudności z wdrażaniem nowych technologii oraz z pozyskiwaniem funduszy zewnętrznych, a także bardziej niż duże ośrodki cierpią z powodu braków kadrowych. Kompleksowa rewitalizacja może służyć jako narzędzie ratujące i stanowić szanse na zdynamizowanie rozwoju całych miast. Jest to jednak proces trudny, związany z dobrą organizacją i koordynacją działań wielu interesariuszy, a także wymagający od nich cierpliwości. Tymczasem w świadomości wielu interesariuszy procesu rewitalizacja łączy się przede wszystkim z aspektami czysto inwestycyjnymi, czyli z natychmiastowym efektem, który łatwo można zaobserwować. Dlatego ważnym wydaje się na wstępie przestudiowanie różnych definicji rewitalizacji, także tej zapisanej w ustawie, i wyłonienie najważniejszych kryteriów tego procesu. Niniejszy tekst ma na celu przeanalizowanie teoretycznych zagadnień związanych z rewitalizacją małych i średnich miast Polski, przestudiowanie ich sieci i genezy. Przedstawienie cech, problemów, uwarunkowań odróżniających je od dużych ośrodków. Celem artykułu jest również zwięzłe przedstawienie ustawy o rewitalizacji, która wprowadza nowe usystematyzowane podejście do rewitalizacji w Polsce, stawiając przed samorządami konkretne zadania i dając im praktyczne narzędzia do jej kompleksowego przeprowadzenia. Jednak z uwagi na to, że ustawa funkcjonuje dopiero od dwóch lat, brak jest jeszcze szczegółowych spraozdań z efektów jej stosowania.

  • Rezerwa subwencji ogólnej w systemie finansowania samorządu terytorialnego
    • Alicja Sekuła
    2017 Full text PRACE NAUKOWE UNIWERSYTETU EKONOMICZNEGO WE WROCŁAWIU

    Artykuł poświęcony jest rezerwie subwencji ogólnej. Jego celem jest analiza jej funkcjonowania w systemie subwencjonowania samorządu terytorialnego pod względem ekonomicznym oraz, częściowo, pod względem prawnym. Podmiotem badań są wszystkie szczeble samorządu terytorialnego: gminny, powiatowy i wojewódzki. Zakres czasowy badań obejmuje lata 2008-2015, natomiast ewolucję rezerwy prześledzono od momentu reaktywacji samorządu terytorialnego, czyli od roku 1991, po czasy współczesne. W artykule wykorzystano metody: statystyki opisowej oraz analizy opisowej. Spośród sformułowanych w pracy wniosków do najistotniejszych należą: brak prawidłowej konstrukcji części „trans-portowo-drogowej” rezerwy, która ma charakter dotacji celowej, a nie subwencji; znaczące różnice w liczbie jednostek-beneficjentów oraz duże fluktuacje kwot rozdzielanych w ramach rezerwy.

  • Rhamnolipid CMC Prediction
    • Ilona Edyta Kłosowska-Chomiczewska
    • Krystyna Mędrzycka
    • Elżbieta Hallmann
    • Karpenko E.
    • Pokynbroda T.
    • Adam Macierzanka
    • Christian Jungnickel
    2017 Full text JOURNAL OF COLLOID AND INTERFACE SCIENCE

    Relationships between the purity, pH, hydrophobicity (log Kow) of the carbon substrate, and the critical micelle concentration (CMC) of rhamnolipid type biosurfactants (RL) were investigated using a quantitative structure–property relationship (QSPR) approach and are presented here for the first time. Measured and literature CMC values of 97 RLs, representing biosurfactants at different stages of purification, were considered. An arbitrary scale for RLs purity was proposed and used in the modelling. A modified evolutionary algorithm was used to create clusters of equations to optimally describe the relationship between CMC and log Kow, pH and purity (the optimal equation had an R2 of 0.8366). It was found that hydrophobicity of the carbon substrate used for the biosynthesis of the RL had the most significant influence on the final CMC of the RL. Purity of the RLs was also found to have a significant impact, where generally the less pure the RL the higher the CMC. These results were in accordance with our experimental data. Therefore, our model equation may be used for controlling the biosynthesis of biosurfactants with properties targeted for specific applications.

  • Rheological characteristics of oligomeric semiproducts gained via chemical degradation of polyurethane foam using crude glycerin in the presence of different catalysts
    • Patrycja Jutrzenka Trzebiatowska
    • Janusz Datta
    2017 Full text POLYMER ENGINEERING AND SCIENCE

    Polyurethane (PU) recycling is a topic of growing interest due to the increasing amount of polyurethane waste. The main purpose of polyurethane chemical recycling is to recover the starting polyol. In this study, a method of polyurethane thermochemical recycling, glycerolysis by means of crude glycerin, is proposed. This work presents a comparative study of commercial catalysts used in order to accelerate the decomposition process, namely triethylamine (TEA), potassium acetate (KAc), 1,4-diazabicyclo[2.2.2]octane (DABCO), sodium hydroxide (NaOH), dibutyltin dilaurate (DbDl), and stannous octoate (StOc).The effect of used catalyst on the chemical structure and rheological properties was studied. The type of catalyst does not have significant influence on the chemical structure, but causes different course of reaction: split- and single-phase in applied conditions. Glycerolysates were measured by Brookfield Rheometer. It was found that repolyols can be described by the Herschel–Bulkely mathematical model in the best accuracy. The investigation showed that the rheological behavior of glycerolysates depended on the catalyst used in glycerolysis process

  • Risk assessment methodologies for pedestrian crossings without traffic lights – Warsaw case study – pedestrian safety assessment
    • Tomasz Mackun
    • Artur Ryś
    • Piotr Tomczuk
    2017 Full text MATEC Web of Conferences

    Based on data from 2015 [1], it was found that 31% of all fatalities in road accidents in Poland were pedestrians. In places accessible to pedestrian traffic 74.2% of total accidents involving pedestrians were recorded. Approximately 53.9% of accidents involving pedestrians take place in the proximity of pedestrian crossings. In the context of improving the safety of vulnerable road users, an assessment of the condition of infrastructure in this sensitive area is very important. Warsaw took up the challenge of a comprehensive assessment of pedestrian crossings in determining the level of road safety and lighting conditions. Research covered pedestrian crossings without traffic lights in three central districts of the city. The work included field research by teams of experts analysing the geometry of pedestrian crossings, their environment and user behaviour. To complete the task, methodologies for assessing risks to pedestrian safety were developed. In this article the authors have attempted to systematise a description of the method of pedestrian safety assessment in the area of pedestrian crossings.

  • Risk Modelling with Bayesian Networks - Case Study: Construction of Tunnel under the Dead Vistula River in Gdansk
    • Beata Grzyl
    • Marian Witold Kembłowski
    • Adam Kristowski
    • Agata Siemaszko
    2017 Full text

    The process of decision-making in public procurement of construction projects during the preparation and implementation phases ought to be supported by risk identification, assessment, and management. In risk assessment one has to take into account factors that lead to risk events (background info), as well as the information about the risk symptoms (monitoring info). Typically once the risks have been assessed a decision-maker has to consider risk-management activities that minimise the risk events (mitigating factors). Finally, the decision-maker has to select best response decision(s), i.e., one that would either maximise the benefits or minimise the losses. This selection is best performed in the framework of the utility theory. Thus, a good diagnostic-decision support model (D-DSM) has to integrate the following elements: background info, risk events, monitoring info, mitigation activities, response decisions, and associated with risk events and decisions utilities. Our purpose is to demonstrate how Bayesian Belief Networks (BBNs) can be used as D-DSM to assess and manage risks, and finally select best response decisions, during the implementation phase of a large construction project. The authors use the example of a road tunnel under the Dead Vistula River in Gdansk (Poland). The D-DSM combines expert knowledge about the relationships among model components with the monitoring information. The model is able to use evidence from various sources in a mathematically rigorous manner. We demonstrate how the model may be used to estimate: the value of monitoring information (from the utility and diagnosis uncertainty perspectives) and the benefits of mitigation activities.

  • River flow simulation based on the HEC-RAS system
    • Zdzisław Kowalczuk
    • Mateusz Świergal
    • Miłosław Wróblewski
    2017

    This work considers the problem of river floods, and presents a computer solution that can be used to predict such a threat. The basic tool, called Hydrologic Engineering Centers for River Analysis System (HEC-RAS), and created by the US Army Corps of Engineering, is well developed; and the models created in the system HEC-RAS are quite realistic. For the purpose of solving practical national flood problems, simplified static and dynamic models of the river Vistula were created in the system HEC-RAS. Furthermore, in this paper, the results of the performed simulations for flood problems in the Vistula basin are presented.

  • RNDM 2016 Workshop and 2nd Meeting of COST CA15127-RECODIS: Highlights from the Resilience Week in Halmstad, Sweden
    • Magnus Jonsson
    • Jacek Rak
    • Dimitri Papadimitriou
    • Arun Somani
    2017 IEEE COMMUNICATIONS MAGAZINE

    Leading network resilience researchers took part in the Resilience Week on Sept. 12-15, 2016 at Halmstad University, SE by Prof. Magnus Jonsson from the Centre for Research on Embedded Systems (CERES), Halmstad University, SE, and Prof. Jacek Rak from Gdansk University of Technology, PL. It included two major events: - The 2nd Meeting of COST CA15127–RECODIS Action (Resilient Communication Services Protecting End-user Applications from Disaster-based Failures, http://www.cost-recodis.eu) held on Sept. 12-13, 2016. - RNDM 2016-8th International Workshop on Resilient Networks Design and Modeling on Sept. 13-15, 2016.