2014 - Publications Repository - Gdańsk University of Technology

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Publications from the year 2014

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Comprehensive distortion compensation of grid-connected inverter currents
- Artur Cichowski
- Piotr Banach
- Wojciech Śleszyński
- Janusz Nieznański
2014
The paper presents a comprehensive approach to the compensation of phase current distortion of grid-connected power inverters. Four different sources of current distortion are addressed: imperfect grid synchronization caused by the distortion in the grid voltages, voltage fluctuations in the dc link, time delays in the estimation of grid voltages, and the distortion of inverter output voltages due to dead-time effects and related factors.
Comprehensive methodology for Staphylococcus aureus lipidomics by liquid chromatography and quadrupole time-of-flight mass spectrometry
- Weronika Hewelt-Belka
- Joanna Nakonieczna
- Mariusz Belka
- Tomasz Bączek
- Jacek Namieśnik
- Agata Kot-Wasik
2014 JOURNAL OF CHROMATOGRAPHY A
Staphylococcus aureus is a common pathogen known to cause relatively minor infections as well as severe disorders in humans. Although there is fair amount of published data concerning various aspects of its biology, epidemiology, genetics, etc., there is still a scarce amount of data presenting reliable and thorough investigations regarding high-throughput analysis of total S. aureus lipid content. Therefore, the aim of this study was to develop an analytical method that in combination with advanced chemometric tools enables comprehensive lipidomic analysis of S. aureus cells. The newly developed method uses high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (LC–Q-TOF-MS) to directly examine extracted lipids and further identify them within a newly developed novel S. aureus lipids database. High coverage of the S. aureus lipidome was obtained by simultaneous bacterial cell lysis and liquid–liquid extraction. The combination of three techniques enabled the analysis of the major membrane lipid classes of S. aureus: separation of the lipid extract in reversed-phase mode, Q-TOF-MS detection in positive ion mode, and lipid database mining. The developed lipidomic approach is also a powerful tool that allows one to assess the lipid content of S. aureus cells in a comparative manner between strains characterized by different phenotypic features as exemplified here by their various sensitivities toward antibiotics.
Comprehensive two-dimensional gas chromatography for determination of the terpenes profile of blue honeysuckle berries
- Magdalena Kupska
- Tomasz Chmiel
- Renata Marcinkowska
- Waldemar Wardencki
- Jacek Namieśnik
2014 FOOD CHEMISTRY
Terpenes are the main group of secondary metabolites, which play essential role in human. The establishment of the terpenes profile of berries of different blue honeysuckle cultivars was achieved by headspace solid-phase microextraction coupled with comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (HS-SPME/GCGC-TOFMS). The berries were found to contain 44 terpenes identified by GCGC-TOFMS. From these, 10 were previously reported in blueberries. According to their chemical structure, the compounds were organized in different groups: monoterpene hydrocarbons and monoterpene oxygen-containing compounds (oxides, alcohols, aldehydes, and ketones). Positive identification of some of the compounds was performed using authentic standards, while tentative identification of the compounds was based on deconvoluted mass spectra and comparison of linear retention indices (LRI) with literature values. The major components of volatile fraction were monoterpenes, such as eucalyptol, linalool and p-cymene. Furthermore, quantitative analysis showed that eucalyptol was the most abundant bioactive terpene in analyzed berries (12.4-418.2 μg/l).
Computational fluid dynamics - lustres and shadows.
- Jerzy Sawicki
2014
The paper is devoted to the different aspects of CFD. The advantages of this concept are evident and obvious; powerfuk and effective tools bring this technology closer to the quantifiable world. However, certain weaknesses in this structure are apparent. Sometimes, a simplistic tendency towards simplifications and facilitations may degenerate and lead to negative behaviours and signs. These have not been serious up to date, but these issues should be pointed out and discussed.
Computational issues of solving the 1D steady gradually varied flow equation
- Wojciech Artichowicz
- Romuald Szymkiewicz
2014 Full text Journal of Hydrology and Hydromechanics
In this paper a problem of multiple solutions of steady gradually varied flow equation in the form of the ordinary differential energy equation is discussed from the viewpoint of its numerical solution. Using the Lipschitz theorem dealing with the uniqueness of solution of an initial value problem for the ordinary differential equation it was shown that the steady gradually varied flow equation can have more than one solution. This fact implies that the nonlinear algebraic equation approximating the ordinary differential energy equation, which additionally coincides with the well-known standard step method usually applied for computing of the flow profile, can have variable number of roots. Consequently, more than one alternative solution corresponding to the same initial condition can be provided. Using this property it is possible to compute the water flow profile passing through the critical stage.
Computational simulation of motion of a rescue module during its launching from ship at rough sea
- Czesław Dymarski
- Paweł Dymarski
2014 Full text Polish Maritime Research
This paper is a continuation of the work titled : “A comp utational model for simulation of motion of rescue module during its launching from stern ramp of a ship at rough sea”. It presents results of computer simulations of motion of a rescue module with embarked persons during its launching on rollers along stern ramp of a ship at rough sea. The simulations were conducted for a selected ship fitted with a launching ramp , for a few selected scenarios of sea conditions. It was assumed that during this operation the ship drifts across direction of wave propagation.
Computationally Efficient Multi-Objective Optimization of and Experimental Validation of Yagi-Uda Antenna
- Adrian Bekasiewicz
- Sławomir Kozieł
- Leifur Leifsson
2014
In this paper, computationally efficient multi-objective optimization of antenna structures is discussed. As a design case, we consider a multi-parameter planar Yagi-Uda antenna structure, featuring a driven element, three directors, and a feeding structure. Direct optimization of the high-fidelity electromagnetic (EM) antenna model is prohibitive in computational terms. Instead, our design methodology exploits response surface approximation (RSA) models constructed from sampled coarse-discretization EM simulation data. The RSA model is utilized to determine the Pareto optimal set of the best possible trade-offs between conflicting objectives. In order toalleviate the difficulties related to a large number of designable parameters, the RSA model is constructed in the initially reduced design space, where the lower/upper parameter bounds are estimated by solving appropriate single-objective problems resulting in identifying the extreme point of the Pareto set. The main optimization engine is multi-objective evolutionary algorithm (MOEA). Selected designs are subsequently refined using space mapping technique to obtain the final representation of the Pareto front at the high-fidelity EM antenna model level. The total design cost corresponds to less than two hundred of EM antenna simulations.
Computations of critical load value of composite shell with random geometric imperfections
- Karol Winkelmann
- Agnieszka Sabik
2014
The work presents the numerical analysis of composite shell with geometric imperfections subjected to compression along its generatrix. The imperfections are described as single indentations and random fields with random parameters of shape and correlation. The fields are generated with the use of the authors made program. Using the authors’ FEM software as well as commercial package Femap with NX Nastran, the critical load values are obtained for the shell with different imperfections. A comparative analysis of the results is performed in terms of change in the loading capacity of the shell.
Computer application for railway track realignment
- Michał Bednarczyk
- Artur Janowski
2014
The topic of this article is the issue of railway track realignment. For this purpose, a computer software application was created that supports computations and generates a report needed for regulation of the trajectory of the railway. This program gives the ability to import data from measurement of the railway trajectory and then perform the calculation of the mathematical realignment. The result of this calculation is the basis for creating a project of the railway track regulation. This program was created in collaborative research project on modernization of railway lines in Poland at the request of one of the railway companies.
Computer-aided Analysis of Induced Sheath Voltages in High Voltage Power Cable System
- Stanisław Czapp
- Krzysztof Dobrzyński
- Jacek Klucznik
- Zbigniew Lubośny
2014
This paper concerns the effect of configuration of high voltage power cables on induced voltages in their metallic sheaths. One, two or three cables per phase and phase sequence of the cables are considered. Computing of the voltages was performed for a normal operation and in case of earth fault. Various ways of the sheaths bonding are considered as well. Shock hazard and voltage stress of non-metallic outer sheath of cables are evaluated. Favourable configurations of the power cable system are indicated.
COMPUTER-AIDED DESIGN OF ORGANOPHOSPHORUS INHIBITORS OF UREASE
- Umesh Kalathiya
- Monikaben Padariya
- L. Berlicki
- Maciej Bagiński
2014 Full text International Journal for Computational Biology
Based on the structure of the most potential inhibitor diamidophosphate, various novel groups of inhibitors were developed by knowledge-based design approach with covalent carbon-phosphorus or carbon-phosphorus-carbon bond to improve hydrolytic stability to inhibit the microbial ureases. Designed compounds were evaluated with 10 (LigScore1, LigScore2, PLP1, PLP2, JAIN, PMF, PMF04, LUDI_1, LUDI_2 and LUDI_3) different scoring functions implemented in Discovery Studio and conformation analysis by AutoDock package.
Computer-Aided Design of Railroad Horizontal Arc Areas in Adapting to Satellite Measurements
- Władysław Koc
- Piotr Chrostowski
2014 JOURNAL OF TRANSPORTATION ENGINEERING-ASCE
This paper presents a method of designing railway sections located in horizontal arcs. The adopted procedure is universal, i.e., it creates the possibility of varying both the type and the length of the assumed transition curves. This means that the applied analytical formulas apply to the boundary conditions of the transition curves and all of the simplifications widely existing in common algorithms have been eliminated. The presented approach is especially useful in the case of analyzing data obtained from continuous satellite measurements. To create the horizontal arc, a calculation algorithm has been implemented in an original computer program that is under the authors’ development. The main features and the results obtained by the use of the program have been described in the paper on the basis of the existing geometrical layout. The authors show the process of designing a particular arc as a sequence of characteristic steps that highlight the problem of assessment. It is shown that the proposed design method allows the generation of the following alternativevariants instantaneously, without any restrictions. The program also includes quality indicators to help assess the practical suitability of particular geometrical layouts.DOI:10.1061/(ASCE)TE.1943-5436.0000643.© 2013 American Society of Civil Engineers.
Computer-Supported Polysensory Integration Technology for Educationally Handicapped Pupils
- Michał Lech
- Andrzej Czyżewski
- Waldemar Kucharski
- Bożena Kostek
2014 LECTURE NOTES IN COMPUTER SCIENCE
In this paper, a multimedia system providing technology for hearing and visual attention stimulation is shortly presented. The system aims to support the development of educationally handicapped pupils. The system has been presented in the context of its configuration, architecture, and therapeutic exercise implementation issues. Results of pupils’ improvements after 8 weeks of training with the system are also provided. Training with the system led to the development of spatial orientation and understanding cause-and-effect relationships.
Concept of Compatibility Region for the Evaluation of IR UWB Electromagnetic Compatibility
- Ryszard Katulski
- Jarosław Sadowski
2014
This paper presents a new proposal for the unified evaluation of ultra wideband and narrowband radio communication systems electromagnetic compatibility, called “compatibility region”. The idea of compatibility region is based on the relation between the ratio of narrowband to ultra wideband signal power in a receiver and some transmission quality indicators (bit error rate, effective data rate).
Conditions of Best Practice Transfer - Results of the Quick IGA Project
- Anita Richert-Kaźmierska
- Marzena Grzesiak
2014
The Quick IGA project supports the development of working and organizational structures in SMEs in order to increase the employment rate of women and elderly and concurrently increases innovation capacities. One of the main project’s tasks was to find best practices from SMEs in Nordic countries in that field (in the first step) and identify (in second step) possibilities and conditions of their implementation in SMEs in other Baltic counties (e.g. Poland, Latvia, Lithuania, Germany). The main aim of this article is to present the results of the project: determinants of chosen practices’ implementation (those focused on prolonging the older persons’ professional activity in Poland, Germany, Lithuania and Latvia).
Consciousness Study of Subjects with Unresponsive Wakefulness Syndrome Employing Multimodal Interfaces
- Bartosz Kunka
- Tomasz Sanner
- Andrzej Czyżewski
- Agnieszka Kwiatkowska
2014
The paper presents a novel multimodal-based methodology for consciousness study of individuals with unresponsive wakefulness syndrome. Two interfaces were employed in the experiments: eye gaze tracking system – CyberEye developed at the Multimedia Systems Department, and EEG device with electrode placement in the international 10-20 standard. It was a pilot study for checking if it is possible to determine objective methods based on multimodal techniques which could replace or support current expensive and difficult to access neuroimaging techniques, like fMRI, PET, utilizing in evaluation of consciousness state. The multimodal-based methodology consists of several phases of research involving subjects. Hearing examination based on objective methods (OAE, ABR), consciousness test based on analysis of visual activity, examination of visual neural pathway with Steady State Visually Evoked Potentials and EEG-based comprehension test were proposed. The results obtained within conducted experiments and presented in this paper suggest that proposed objective-subjective methodology could potentially be introduced into clinical facilities after further validation.
Conserved motifs of MutL proteins
- Michał Banasik
- Paweł Sachadyn
2014 MUTATION RESEARCH-FUNDAMENTAL AND MOLECULAR MECHANISMS OF MUTAGENESIS
tThe MutL protein is best known for its function in DNA mismatch repair (MMR). However, there isevidence to suggest that MutL is not only the linker connecting the functions of MutS and MutH in MMR,but that it also participates in other repair systems, such as Very Short Patch (VSP), Base Excision (BER)and Nucleotide Excision Repair (NER). This study set out to identify the most highly conserved aminoacid sequence motifs in MutL proteins.We analyzed 208 MutL amino acid sequences of 199 representative prokaryotic species belonging to28 classes of bacteria and archaea. The analysis revealed 16 conserved motifs situated in the ATPaseand endonuclease domains, as well as within the disordered loop, and in the MutL regions interactingwith the clamp of DNA polymerase III. The conserved sequence motifs thus determined constitutea structural definition of MutL and they may be used in site-directed mutagenesis studies. We foundconserved residues within the potential regions where binding with MutS occurs. However, the existingdata does not provide clues as to the possible sites of MutL interactions with the proteins involved inother DNA repair systems such as NER, BER and VSP.We determined the 57 most highly conserved amino acid residues, including 43 which were identicalin all the sequences analyzed. The greater part of the most predominantly conserved amino acid residuesidentified in MutL are identical to the corresponding residues reported as mutational hot-spots in one ofits human homologues, MLH1, but not in the other, PMS2.This is the first study to present the conserved sequence motifs of MutL widespread in bacteria andarchaea and the classification of MutLs into five groups distinguished on the basis of differences in theC-terminal region. Our analysis is of use in better understanding MutL functions.
Consolidating logs in varying formats into a structured repository = konsolidacja logów w zmiennych formatach do strukturalnego repozytorium
- Artur Opaliński
2014 Studia Informatica Pomerania
During multi-agent systems development, testing and re- search, possibly voluminous logs are created at distributed agent loca-tions. These logs describe individual agents behavior and state changes. To get the complete picture of the multi-agent system working, it is necessary to consolidate these logs and to store them in a format appropriate for diverse analyzes. Specic issues arise during consolidation if the log formats are not uniform. This paper presents an approach to consolidate logs in various formats into a single repository suitable for further analyzes.
Construction of tournament robot Mirror taking part in Mini Sumo competition
- Tymoteusz Cejrowski
- Paczyński Mateusz
- Dawid Machala
2014 Full text Pomiary Automatyka Robotyka
W artykule zaprezentowano projekt budowy robota turniejowego, startującego w zawodach Mini Sumo. Omówiono założenia dyscypliny Mini Sumo oraz konstrukcję mechaniczną, algorytmy sterujące i elektronikę zawartą w robocie.
Constructive entanglement test from triangle inequality
- Łukasz Rudnicki
- Zbigniew Puchała
- Paweł Horodecki
- Karol Życzkowski
2014 Journal of Physics A-Mathematical and Theoretical
We derive a simple lower bound on the geometric measure of entanglement for mixed quantum states in the case of a general multipartite system. The main ingredient of the presented derivation is the triangle inequality applied to the root infidelity distance in the space of density matrices. The obtained bound leads to entanglement criteria with a straightforward interpretation. The proposed criteria provide an experimentally accessible, powerful entanglement test.