2018 - Publications Repository - Gdańsk University of Technology

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Publications from the year 2018

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Machining process sequencing and machine assignment in generative feature-based CAPP for mill-turn parts
- Mariusz Deja
- Mieczysław Siemiątkowski
2018 Full text JOURNAL OF MANUFACTURING SYSTEMS
Process selection and sequencing, as one of the most complex issues when evaluated from a mathematical point of view and crucial in CAPP, still attract research attention. For the current trend of intelligent manufacturing, machining features (MFs) are the information carriers for workpiece geometry and topology representation. They are basically derived from CAD models and are used by downstream engineering applications. A feature-based reasoning approach for generating machining sequences in terms of part setups and the assignment of machine alternatives is presented. The approach suggested in this research assumes a heavy reliance on a data input model incorporating functional requirements for parts and in particular GD&T references. An extended feature taxonomy corresponding to the needs of the rational process plan selection for the addressed category of part types is proposed. It is meant to be applicable to machining of both rotational and prismatic features using machines of various configurations. The developed taxonomy is based on the working directions for MFs and includes the identification of their location with respect to datum references. The developed taxonomy that involves feature tolerance relationships is at the core of the information data model utilised by the original algorithm which was aimed at generic process sequencing for the definite category of mechanical parts. Through the developed algorithm, adequate process alternatives can be generated by adaptive setup merging on a single machine or across multiple available machines under consideration of their respective process capabilities. The approach has been validated through an illustrative case study using a sample mill-turn part of considerable complexity.
Macierzowa analiza konstrukcji prętowych w środowisku MATLAB®
- Magdalena Rucka
- Stanisław Burzyński
- Agnieszka Sabik
2018
Niniejsza książka poświęcona jest metodzie przemieszeń w ujęciu macierzowym, znanej także pod nazwą bezpośredniej lub komputerowej metody przemieszczeń. Podejście to jest szczególnym przypadkiem metody elementów skończonych (MES), która jest od wielu lat powszechnie stosowana w działalności inżynierskiej, w tym do analizowania różnorodnych problemów mechaniki. Metoda przemieszczeń jest dedykowana rozwiązywaniu układów prętowych. Podstawową zaletą tej metody jest prostota podstaw teoretycznych, które omawiane są podczas kursów mechaniki budowli i wytrzymałości materiałów. Nie jest w tym przypadku wymagana niezbędna wiedza z zakresu mechaniki ośrodków ciągłych. Z tego względu metoda przemieszczeń nadal stanowi doskonałą podstawę do nauki metod komputerowych w mechanice konstrukcji. W dobie rozkwitu komercyjnych programów MES przyswojenie podstaw komputerowego rozwiązywania problemów mechaniki jest kluczowe dla ich efektywnego wykorzystywania. Zakres opracowania obejmuje opis teoretyczny oraz praktyczne przykłady problemów statyki, stateczności oraz analizy modalnej układów prętowych w formie zadań i przykładowych rozwiązań w środowisku MATLAB®. Wybrane fragmenty programów umieszczono w tekście, a wszystkie programy i procedury dostępne są pod adresem internetowym http://wilis.pg.edu.pl/kwm/ksiazki
Magiczne światło - koncept HCL
- Natalia Sokół
2018 Full text Oświetlenie LED
Światło od wieków kojarzone było ze strefą sacrum, zjawiskiem nie do końca poznanym mistycznym i magicznym. Twórcy dzieł artystycznych lub architektonicznych często odwoływali się do konotacji świetlnych, próbując oddać relacje człowieka z rzeczywistością pozamaterialną lub pozazmysłową, oraz stworzyć wnętrza inspirujące takie przeżycia. Pomimo mistycznej otoczki światło jako zjawisko fizyczne zostało opisane językiem technicznym i scharakteryzowane wielkościami fotometrycznymi. Ale jak pokazują ostatnie badania, techniczny opis światła, jego właściwości i oddziaływania okazał się niewystarczający.
Magnetic field effects in dye-sensitized and organic solar cells
- Maciej Klein
2018 Full text
The charge recombination and exciton dissociation are generally recognized as the basic electronic processes limiting the efficiency of photovoltaic devices. The aim of this thesis is to understand the electronic processes limiting the operation of efficient solar cells with particular emphasis on the role of electronic states endowed with magnetic dipole moment. The research work is divided into two parts. The first part deals with dye-sensitized solar cells (DSSCs) with sensitizers based on organic molecules (squaraine) and ruthenium complexes, while the second one regards organic solar cells (OSC) of a single-layer (squaraine) and bulk-heterojunction (squaraine:fullerene) architecture. A detailed mechanism of photocurrent generation in investigated solar cells systems examined by magnetic field effect (MFE) technique is proposed. The observed MFE in DSSCs is attributed to magnetic-field-induced spin-mixing of singlet and triplet electron-hole (e-h) pairs according to the Δg mechanism with spin dephasing due to different Lande g factors of the electron and hole entities. In OSCs under a weak external magnetic field, the change in photocurrent is due to electron and hole (e-h) pairs that experience a modulating hyperfine interaction associated with nuclear (mainly proton) magnetic moments, while in strong magnetic fields the photocurrent is affected by the Δg mechanism.
Magnetic field gradient as the most useful signal for detection of flaws using MFL technique
- Zbigniew Usarek
- Marek Chmielewski
- Leszek Piotrowski
2018 Full text Journal of Electrical Engineering
The magnetic flux leakage (MFL) technique is extensively used for detection of flaws as well as for evaluation of their dimensions in ferromagnetic materials. However, proper analysis of the MFL signal is hindered by the MFL sensor velocity causing distortions of this signal. Traditionally measured components of the MFL signal are particularly sensitive to the scanning velocity. In this paper, an another signal – the gradient of the normal component of magnetic flux density – was proposed as it is less sensitive to the scanning velocity. Results obtained for scans of the steel plate with artificially manufactured flaws confirm this statement.
Magnetoacoustic heating in a quasi-isentropic magnetic gas
- Anna Perelomova
2018 Full text PHYSICS OF PLASMAS
The nonlinear heating of a plasma which associates with the transfer of energy of magnetoacoustic waves into that of the entropy mode, is analytically studied. A plasma is uniform and motionless at equilibrium. Perturbations in a plasma are described by a system of ideal magnetohydrodynamic equations. The equilibrium straight magnetic strength and the wave vector form a constant angle which varies from 0 to π/2. There exist four magnetosound branches (two slow and two fast) which differ by the speed and direction of propagation in this geometry. Various cases of a nonlinear flow take place due to the kind of external source of energy. This may make plasma isentropically or/and thermally unstable. We consider magnetoacoustic heating which is excited by any one of the magnetosound perturbations in the different cases of a flow. The nonlinear instantaneous equations, which describe the dynamics of the entropy mode in the field of intense magnetoacoustic perturbations, are analytically derived and discussed in regard to some physically meaningful cases. We use special projecting in order to derive weakly nonlinear evolutionary equations.
Magnetoacoustic Heating in Nonisentropic Plasma Caused by Different Kinds of Heating-Cooling Function
- Anna Perelomova
2018 Full text Advances in Mathematical Physics
The nonlinear phenomena which associate with magnetoacoustic waves in a plasma are analytically studied. A plasma is an open system with external inflow of energy and radiation losses. A plasma’s flow may be isentropically stable or unstable. The nonlinear phenomena occur differently in dependence on stability or instability of a plasma’s flow. The nonlinear instantaneous equation which describes dynamics of nonwave entropy mode in the field of intense magnetoacoustic perturbations is the result of special projecting of the conservation equations in the differential form. It is analyzed in some physically meaningful cases; those are periodic magnetoacoustic perturbations and particular cases of heating-cooling function. A plasma is situated in the straight magnetic field with constant equilibrium magnetic strength which form constant angle with the direction of wave propagation. A plasma is initially uniform and equilibrium. The conclusions concern nonlinear effects of fast and slow magnetoacoustic perturbations and may be useful in direct and inverse problems.
Main complications connected with detection, identification and determination of trace organic constituents in complex matrix samples
- Natalia Jatkowska
- Małgorzata Rutkowska
- Katarzyna Owczarek
- Justyna Płotka-Wasylka
- Jacek Namieśnik
2018 TRAC-TRENDS IN ANALYTICAL CHEMISTRY
It is well known that some problems with the determination of organic analytes at trace level can occur. This issue is connected with contamination during each stage of the analytical procedure from sampling to sample preparation up to chromatographic analysis, which often leads to false-positive or overestimated results. Another problem associated with determination of analytes occurs at trace- and ultra-trace level is a background problem which is mainly dictated by techniques, glassware and solvents. This review provides information on main complications connected with determination of trace organic constituents in complex matrix samples. Error sources in the field of determination of trace analytes are described in detail. In addition, the type of the background in each of the stapes of analytical procedure is summarized.
Main Outlines of Lightning Research Development in Poland
- Zdobysław Flisowski
- Marek Łoboda
- Grzegorz Masłowski
- Stanisław Wojtas
2018
The paper deals with the historical development of lightning protection research, lightning protection ideas and investigations in Poland. The main achievements of lightning research performed at the technical universities in Gdansk, Warsaw and Rzeszow have been characterized. Exemplary main achievements related to natural lightning observations and measurements as well to those performed in laboratory scale tests have been shortly described.
Main strategies, analytical trends and challenges in LC-MS and ambient mass spectrometry-based metabolomics
- Justyna Aszyk
- Hubert Byliński
- Jacek Namieśnik
- Agata Kot-Wasik
2018 TRAC-TRENDS IN ANALYTICAL CHEMISTRY
A plethora of analytical LC-MS-based methods have been successfully applied to analyses of complex samples of various origin for metabolomics investigations. Over the last ten years, the substantial evolution of ambient mass spectrometry (AMS) techniques has highlighted their tremendous potential in metabolomic studies due to the minimal sample pretreatment requirement and the ability to analyse samples in their native state. This review illustrates the present state of the art in application of the LC-MS- and AMS-based techniques in various fields of metabolomics. We focused on the AMS-based techniques that have most commonly been applied in metabolomicsstudies. Our review covers the main strategies and challenges identified in the implementation of these approaches, as well as key limiting factors, such as sample preparation, ionization techniques and quantitation capabilities. We believe that the present paper represents the first attempt to compare these two approaches and will be useful in future metabolomics studies.
Make lighting healthier
- Karolina Zielińska-Dąbkowska
2018 NATURE
Life on Earth evolved in day-and-night cycles. Plants and animals, including insects such as the fruit fly, have a biological clock that controls their circadian rhythms — as the 2017 winners of the Nobel Prize in Physiology or Medicine showed. Now, humans’ increasing reliance on artificial lighting is changing those rhythms.
MaliciousIDE – software development environment that evokes emotions
- Michał Wróbel
- Adam Zielke
2018 Full text Annals of Computer Science and Information Systems
Emotions affect every aspect of human live, including work. Numerous studies in software engineering have shown that negative emotions can lower the productivity of programmers. Unlike traditional approaches to managing software development, modern methods, such as Agile and Lean, take into account human aspects of programming. To thoroughly investigate the impact of negative emotions on the work of programmers, a malicious integrated development environment (IDE) was developed. This tool allow a observer to trigger malicious behavior of the IDE. Conducted study have proved its usefulness. Participants reported that it mostly invoked frustration and angry
Mamy po prostu być. Spotkania z Tosią i jej matematycznym "baranem"
- Katarzyna Weinerowska-Bords
2018
Artykuł dotyczy tutoringu czyli szczególnej metody pracy z podopiecznym, którą cechuje spersonalizowane i całościowe podejście do ucznia oraz troska o optymalny rozwój jego samoświadomości i potencjału. Artykuł wpisuje się w zbiór prac o charakterze studium przypadku.
Managing Quality Contests Based on Excellence Model at the Local Level. Selected Conditions and Problems – Case Study
- Piotr Grudowski
- Anna Wendt
2018 Full text Annales Universitatis Mariae Curie-Skłodowska, Sectio H Oeconomia
The aim of this article was to present characteristic phenomena accompanying competitions for quality awards based on the use of the organizational excellence models implemented at the regional level. Typical problems were identified, the understanding of which allows for a better use of the idea of excellence to raise the overall level of maturity of organizations aspiring to quality awards at every level. The results of self-assessment and external verification of organizations participating in the 21st edition of the Competition for the Pomeranian Quality Award were presented. On the basis of in-depth interviews with employees of the competition organizing unit as well as source materials, a diagnosis of the current state concerning this undertaking was presented and some directions of improvement actions were defined.
Manganese Phosphatizing Coatings: The Effects of Preparation Conditions on Surface Properties
- Jakub Duszczyk
- Katarzyna Siuzdak
- Tomasz Klimczuk
- Judyta Strychalska-Nowak
- Adriana Zaleska-Medynska
2018 Full text Materials
Manganese phosphate coating could be used to protect the surface of steel products. However, it is essential to determine the effects which process parameters, as well as the types of additives used, have on the efficiency of coating deposition. Thus, we present here a process of phosphatization of low-alloy steel (for 15 min at 95 ◦C) in manganese/nickel baths followed by a passivation process with the use of a silicon and zircon compounds. The microstructure and morphology of the surface were analyzed by SEM EDX and XRD methods. The obtained results showed that the manganese phosphate could be effectively formed at 95 ◦C in the solution containing nickel and guanidine derivatives. Anodic polarization of manganese coating was investigated in 0.5 M KCl by the analysis of polarization resistance. The effects of the activation process on corrosion properties of the coating have been examined. It was observed that an increased concentration of activating substances in the activation bath results in the enhancement of corrosion resistance.
Manufacturing Data Analysis in Internet of Things/Internet of Data (IoT/IoD) Scenario
- Edward Szczerbicki
- Syed Imran Shafiq
- Cesar Sanin
2018 Full text CYBERNETICS AND SYSTEMS
Computer integrated manufacturing (CIM) has enormous benefits as it increases the rate of production, reduces errors and production waste, and streamlines manufacturing sub-systems. However, there are some new challenges related to CIM operating in the Internet of Things/Internet of Data (IoT/IoD) scenarios associated with Industry 4.0 and cyber-physical systems. The main challenge is to deal with the massive volume of data flowing between various CIM components functioning in virtual settings of IoT. This paper proposes decisional DNA-based knowledge representation framework to manage the storage, analysis, and processing of data, information, and knowledge of a typical CIM. The framework utilizes the concept of virtual engineering object and virtual engineering process for developing knowledge models of various CIM components such as automatic storage and retrieval systems, automatic guided vehicles, robots, and numerically controlled machines. The proposed model is capable of capturing in real time the manufacturing data, information and knowledge at every stage of production, that is, at the object level, the process level, and at the factory level. The significance of this study is that it will support decision-making by reusing the experience, which will not only help in effective real-time data monitoring and processing, but also make CIM system intelligent and ready to function in the virtual Industry 4.0 environment.
Marking the Allophones Boundaries Based on the DTW Algorithm
- Janusz Rafałko
2018
The paper presents an approach to marking the boundaries of allophones in the speech signal based on the Dynamic Time Warping (DTW) algorithm. Setting and marking of allophones boundaries in continuous speech is a difficult issue due to the mutual influence of adjacent phonemes on each other. It is this neighborhood on the one hand that creates variants of phonemes that is allophones, and on the other hand it affects that the border between allophones is in some cases very difficult to determine. Nowadays, this task is carried out manually in cooperation with specialists in the field of phonetics. The presented approach allows to build a system that is able to automate this process. The aim of the work currently carried out by the author is a method that facilitates the training material processing for the needs of the development of multimodal speech recognition systems. For this purpose, the difficult problem of marking boundaries of allophones is solved in this report based on the Polish dictionary in the context of the creation of allophone bases for speech synthesis. This is done in this way due to the simplified possibility of organizing critical listening and subjective evaluation of received allophones by a large group of Polish native speakers (75 people). Strengthening the method will allow it to be used for the extraction of allophones for the needs of developed system of automatic transcription of English speech and for its notation according to the IPA standard. The analyzed continuous speech is combined in the DTW algorithm with a synthesized speech signal. The comparison of both signals is perform not in the time domain as in the classical DTW, but in the frequency domain. This allows for a statement that the phonetic content of both signals is compared. The paper describes the process of marking the boundaries of allophones for the Polish language, however after appropriate modifications, this approach can be used to determine the allophones boundaries in other languages, especially for English.
MARSTRUCT benchmark study on nonlinear FE simulation of an experiment of an indenter impact with a ship side-shell structure
- Jonas Ringsberg
- Jörgen Amdahl
- Bai Chen
- Sang-Rai Cho
- Sören Ehlers
- Zhiqiang Hu
- Jan Kubiczek
- Mihkel Kõrgesaar
- Bin Liu
- Janis Marinatos
- Karol Niklas
- Joško Parunov
- Bruce Quinton
- Smiljko Rudan
- Manolis Samuelides
- Carlos Soares
- Kristjan Tabri
- Richard Villavicencio
- Yasuhira Yamada
- Zhaolong Yu
- Shengming Zhang
2018 MARINE STRUCTURES
This paper presents a benchmark study on collision simulations that was initiated by the MARSTRUCT Virtual Institute. The objective was to compare assumptions, finite element models, modelling techniques and experiences between established researchers within the field. Fifteen research groups world-wide participated in the study. An experiment involving a rigid indenter penetrating a ship-like side structure was used as the case study. A description of how the experiment was performed, the geometry model of it, and material properties were distributed to the participants prior to their simulations. The paper presents the results obtained from the fifteen FE simulations and the experiment. It presents a comparison of, among other factors, the reaction force versus the indenter displacement, internal energy absorbed by the structure versus the indenter displacement, and analyses of the participants' ability to predict failure modes and events that were observed in the experiment. The outcome of the study is a iscussion and recommendations regarding mesh size, failure criteria and damage models, interpretation of material data and how they are used in a constitutive material model, and finally, uncertainties ingeneral.
Mashup Approaches for Improving Service Oriented Business Scenarios
- Henryk Krawczyk
- Narek Parsamyan
2018 Full text TASK Quarterly
Two kinds of business scenarios are considered: application- and service-oriented. It is shown that the former are more flexible and easier reconfigurable for both traditional (human-oriented) and IT services. Moreover, complex IT services can be created by simple IT services using the modern mashup technology. It is the reason why such business scenarios can be modeled by BPMN in much easier ways. A simple example of a supply chain of a sales company is considered and the available advantages of such technologies are emphasized in the paper.
Massive Open Online Courses (MOOCs) in hospitality and tourism
- Jamie Murphy
- Nadzeya Kalbaska
- Lorenzo Cantoni
- Laura Horton-Tognazzini
- Peter Ryan
- Alan Williams
2018
The tourism industry, interesting and challenging, faces structural human resource problems such as skills shortages and staff turnover, seasonality and a high percentage of small to medium enterprises whose employees have limited time for training or education. Large tourism enterprises often span countries and continents, such as hotel chains, airlines, cruise companies and car rentals, where the employees need similar training — a costly activity. Although hospitality and tourism educational resources have expanded and evolved during the last two decades, online courses — particularly free and open courses — remain limited. Electronic learning (eLearning) can help address some of these training issues (Cantoni et al., 2009; Kalbaska, 2012; Kuttainen and Lexhagen, 2012; Sigala, 2002).