2015 - Repozytorium publikacji - Politechnika Gdańska

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Publikacje z roku 2015

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Combined analysis of whole human blood parameters by Raman spectroscopy and spectral-domain low-coherence interferometry
- Marcin Gnyba
- Maciej Wróbel
- Katarzyna Karpienko
- Daria Majchrowicz
- Małgorzata Szczerska
2015
In this article the simultaneous investigation of blood parameters by complementary optical methods, Raman spectroscopy and spectral-domain low-coherence interferometry, is presented. Thus, the mutual relationship between chemical and physical properties may be investigated, because low-coherence interferometry measures optical properties of the investigated object, while Raman spectroscopy gives information about its molecular composition. A series of in-vitro measurements were carried out to assess sufficient accuracy for monitoring of blood parameters. A vast number of blood samples with various hematological parameters, collected from different donors, were measured in order to achieve a statistical significance of results and validation of the methods. Preliminary results indicate the benefits in combination of presented complementary methods and form the basis for development of a multimodal system for rapid and accurate optical determination of selected parameters in whole human blood. Future development of optical systems and multivariate calibration models are planned to extend the number of detected blood parameters and provide a robust quantitative multi-component analysis.
Comparative Analysis of Numerical and Experimental Studies of the Airflow Around the Sample of Urban Development
- Katarzyna Zielonko-Jung
- Marta Poćwierz
- Konrad Gumowski
- Olszewski Oskar
2015 Pełny tekst Bulletin of the Polish Academy of Sciences-Technical Sciences
In this paper, on the background of a short overview of the recent advances in the field of Environmental Wind Engineering (EWE), a comparison of wind tunnel experiment and numerical simulation for some cases of airflow around an urban layout have been reported. The purpose of the study is quantitative and qualitative comparison of measurements in the wind tunnel as well as numerical simulation using Ansys Fluent software. The study is concerned mostly with the analysis of parameters which are essential in the building industry, such as pressure and velocity fields. In the numerical analysis the k-ε realizable model of turbulence with the basic model of boundary layer – Standard Wall Treatment, were used. Particular attention has been paid to accurate depiction of the conditions on the inlet and the selection of suitable computing.
Comparative molecular modelling of biologically active sterols
- Mariusz Baran
- Jan Mazerski
2015 JOURNAL OF MOLECULAR STRUCTURE
Membrane sterols are targets for a clinically important antifungal agent – amphotericin B. The relatively specific antifungal action of the drug is based on a stronger interaction of amphotericin B with fungal ergosterol than with mammalian cholesterol. Conformational space occupied by six sterols has been defined using the molecular dynamics method to establish if the conformational features correspond to the preferential interaction of amphotericin B with ergosterol as compared with cholesterol. The compounds studied were chosen on the basis of structural features characteristic for cholesterol and ergosterol and on available experimental data on the ability to form complexes with the antibiotic. Statistical analysis of the data obtained has been performed. The results show similarity of the conformational spaces occupied by all the sterols tested. This suggests that the conformational differences of sterol molecules are not the major feature responsible for the differential sterol – drug affinity.
COMPARISION OF TWO WIND FARMS CONSTRUCTION PROJECTS USING F-AHP METHODP
- Alicja Stoltmann
2015 Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej
Referat przedstawia porównanie projektów dwóch farm wiatrowych. Częścią referatu jest opis kryteriów, które muszą zostać uwzględnione w trakcie analizy porównawczej projektów budowy FW. Tego typu analiza znajduje zastosowanie w przypadku zakupu projektów inwestycyjnych będących w fazie przygotowania. Spowodowane jest to koniecznością uwzględnienia wymogów określonych w ustawodawstwie polskim dotyczących np. prawa do terenu, uwarunkowań środowiskowych itd. dla farmy wiatrowej wraz z infrastrukturą towarzyszącą oraz kompletu dokumentów dla wyprowadzenia wyprodukowanej energii elektrycznej do sieci elektroenergetycznej. W analizie uwzględniono także problematykę zawarcia umowy przyłączeniowej z operatorem systemu przesyłowego lub dystrybucyjnego. Aby zweryfikować, na jaki etap należy zwrócić szczególną uwagę posłużono się analizą kryteriów opisujących poszczególne etapy i zadania realizowane w poszczególnych etapach. Analizę przeprowadzono z wykorzystaniem metody F-AHP, która pozwala na ilościowe i jakościowe uporządkowanie kryteriów.
Comparison of active proximity radars for the wearable devices
- Adam Bujnowski
- Krzysztof Czuszyński
- Jacek Rumiński
- Jerzy Wtorek
- Roderick McCall
- Andrei Popleteev
- Nicolas Louveton
- Thomas Engel
2015
Two methods of object position and movement estimation in relation to the user of smart glasses were investigated. An active infrared and ultrasonic methods of the obstacle detection were presented and compared. Application of these methods depend on active transducers type (physical medium used), geometry and surface properties of detected objects and their movement direction and speed. In the article properties of both detectors were compared and applicability of both methods in mobile, battery operated environment such as eGlasses platform were compared.
Comparison of calculated and measured thermal stresses in asphalt concrete
- Marek Pszczoła
- Józef Judycki
2015 Pełny tekst Baltic Journal of Road and Bridge Engineering
The paper presents the comparison of calculated and measured thermal stresses induced in restrained asphalt concrete specimens by cooling. Thermal stresses were measured in the Thermal Stress Restrained Specimen Test. The calculations of thermal stresses were performed with the use of a theoretical formula based on the temperature dependent stiffness modulus. The novel approach applied in this paper was that the stiffness modulus of asphalt concrete which was used in calculations was measured in a creep test at low temperatures on the same material which was used in the Thermal Stress Restrained Specimen Test. Realistic values of stiffness moduli resulted in a good compatibility between calculated and measured thermal stresses. The creep test at low temperatures was performed in bending according to the method developed at the Gdansk University of Technology. Three types of bitumen were used to produce asphalt concrete. The lowest thermal stresses were induced in the Thermal Stress Restrained Specimen Test in asphalt concrete with 50/70 multigrade bitumen, next with DE 80B SBS polymer modified bitumen and the highest with 50/70 plain bitumen.
Comparison of PCBs and PAHs levels in European coastal waters using mussels from the Mytilus edulis complex as biomonitors
- Michał Olenycz
- Adam Sokołowski
- Agnieszka Niewińska
- Maciej Wołowicz
- Jacek Namieśnik
- Herman Hummel
- Jeroen Jansen
2015 Pełny tekst OCEANOLOGIA
Mussels from the Mytilus edulis complex were used as biomonitors for two groups of organic pollutants: polychlorinated biphenyls (PCBs, congeners: 28, 52, 101, 118, 138, 153 and 180) and polycyclic aromatic hydrocarbons (PAHs, naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, indeno(1,2,3-cd)pyrene, dibenz(a,h)anthracene, benzo(g,h,i)perylene) at 17 sampling sites to assess their relative bioavailabilities in coastal waters around Europe. Because of the temporal differences in PCBs and PAHs concentrations, data were adjusted using Seasonal Variation Coefficients (SVC) before making large-scale spatial comparisons. The highest concentrations of PCBs were found near estuaries of large rivers flowing through urban areas and industrial regions. Elevated bioavailabilities of PAHs occurred in the vicinity of large harbors, urban areas, and regions affected by petroleum pollution as well as in some remote locations, which indicated long-range atmospheric deposition.
COMPARISON OF SYSTEM ON CHIP TECHNOLOGIES FOR SPACE APPLICATIONS
- Bogdan Pankiewicz
- Marek Wójcikowski
- Stanisław Szczepański
2015
The paper presents a review of technologies available for the implementation of digital and mixed signal systems, particularly the system on a chip (SoC) for space applications. The phenomena encountered in the space environment are briefly presented, together with the known solutions, regarding the design of complex electronic systems. The most important norms regarding single die integrated circuits designed for space are also mentioned. The authors, having experience in the design of microelectronic systems in FPGA (Field Programmable Gate Array) and ASIC (Application Specific Integrated Circuit) technologies; present and compare the possible solutions that are available for harsh environments, such as space. The design for space application may be effectively achieved through a careful choice within radiation tolerant technology. The adaptation of the designs for space applications is achieved by suitable device and technology selection and appropriate design techniques. This is relatively easy for the design, team experienced in non-space designs. Another very important element is the sensor miniaturisation, where for this purpose the MEMS (Micro Electro-Mechanical Systems) are very convenient. A table with the comparison of various technologies suitable for space applications from leading manufacturers is also presented.
COMPARISON OF THE ABRASION RESISTANCE OF THE SELECTED BIOMATERIALS FOR FRICTION COMPONENTS IN ORTHOPEDIC ENDOPROSTHESES
- Katarzyna Zasińska
- Tomasz Seramak
- Jacek Łubiński
2015 Pełny tekst TRIBOLOGIA
Rosnące z każdym rokiem zapotrzebowanie na endoprotezy stawów ortopedycznych przy jednoczesnym dążeniu do zwiększenia ich trwałości i wyeliminowania negatywnych skutków ubocznych produktów zużycia, które mogą wywoływać proces zapalny w tkankach determinuje potrzebę poszukiwania nowych biomateriałów, bądź metody modyfikacji ich powierzchni. Nadrzędnym celem prowadzonych przez nas badań było oszacowanie intensywności zużycia ściernego biomateriałów obecnie stosowanych na pary trące w endoprotezach ortopedycznych oraz nowego stopu tytanu Ti13Nb13Zr w aspekcie zastosowania go na elementy trące endoprotez. Do badań użyto czterech biomateriałów metalicznych: stopu Ti13Nb13Zr, stali nierdzewnej 316 LVM, stopu CoCrMo oraz stopu Ti6Al4V. Materiałem przeciwpróbki był polietylen o ultra wysokiej wadze cząsteczkowej (PE-UHMW). Ocenę odporności na zużycie ścierne badanych biomateriałów dokonano na podstawie wyznaczania wartości współczynnika tarcia dla konkretnej pary trącej, zmierzenia profili chropowatości powierzchni oraz obserwacji mikroskopowych (LM).
Comparison of the impact test and the harmonic test in measurements of natural resonant frequencies of circular saw blades
- Anna Danuta Kaczmarek-Peniakova
- Lubomir Javorek
- Kazimierz Orłowski
2015 Pełny tekst Annals of WULS, Forestry and Wood Technology
In this paper results of measurements of natural resonant frequencies of circular saw blades with the impact test and the harmonic test are presented. Comparison of these two methods revealed that during testing of circular saw blades, in which bodies the open and closed notches (cuts) for cleaning of knives are present, with the harmonic test method it has been observed appearing of quasi-twin resonant frequencies, whereas the impact test method could not allow to recognize them , because it does not clearly confirm the occurrence of such frequencies.
Comparison of the powers of energy losses in a variable capacity displacement pump determined without or with taking into account the power of hydraulic oil compression
- Zygmunt Paszota
2015 Pełny tekst Polish Maritime Research
Powers of energy losses in a variable capacity displacement pump are compared with or without taking into account the power of hydraulic oil compression. Evaluation of power of liquid compression in the pump was made possible by the use of method, proposed by the Author, of determining the degree of liquid aeration in the pump. In the method of determining the liquid aeration in the pump and of powers of volumetric losses of liquid compression a simplified formula was used describing the field of indicated work of volumetric losses of liquid compression during one shaft revolution at indicated increase of pressure in the chambers. Three methods were used for comparing the sum of powers of volumetric losses due to leakage and of compression and also of mechanical losses resulting from increase of indicated pressure in the working chambers.
Comparison of tuning procedures based on evolutionary algorithm for multi-region fuzzy-logic PID controller for non-linear plant
- Bartosz Puchalski
- Tomasz Adam Rutkowski
- Jarosław Tarnawski
- Kazimierz Duzinkiewicz
2015
The paper presents a comparison of tuning procedures for a multi-region fuzzy-logic controller used for nonlinear process control. This controller is composed of local PID controllers and fuzzy-logic mechanism that aggregates local control signals. Three off-line tuning procedures are presented. The first one focuses on separate tuning of local PID controllers gains in the case when the parameters of membership functions of fuzzy-logic mechanism are know a priori. The second one consists of two major steps. In the first step, the local PID controllers gains are calibrated and in the next step the parameters of membership functions of fuzzy-logic mechanism are tuned. The third one focuses on tuning of PID controllers gains and membership functions parameters jointly. These procedures exploit evolutionary algorithm to optimize the performance of the multi-region fuzzylogic controller with respect to integral quality criterion such as Integral Absolute Error (IAE). Effectiveness of these procedures is verified based on a well known from literature continuous nonlinear pH neutralization reactor model. For comparison a single PID controller tuned for specific work point is also taken into account.
Compensation of Dead Time Effects for Shunt Active Power Filters
- Artur Cichowski
- Wojciech Śleszyński
- Janusz Nieznański
- Paweł Szczepankowski
2015
The paper presents a comprehensive approach to the compensation of the grid current distortion for shunt active power filter systems. Four different sources of current distortion are addressed: imperfect grid synchronization caused by the distortion in the grid voltages, time delays in the estimation of compensating currents and grid voltages, fluctuations of the dc bus voltage, and the distortion of inverter output voltages due to dead-time effects and related factors. The focus of the paper is on the assessment of the significance of the dead time compensation.
Compensation of magnetic disturbances caused by sensors in a differential magnetometric system
- Kazimierz Jakubiuk
- Mirosław Wołoszyn
- Marek Chomnicki
- Jacek Łubkowski
2015 Pełny tekst Przegląd Elektrotechniczny
Study of low magnetic fields necessitates the use of precision magnetometers working in a differential system. Minimization of this error is a substantial issue in the case of magnetometers working in a differential system on a mobile platform. The compensation method of heading error consists in taking measurements of changes in magnetic induction with the use of the tested magnetometer for various locations of the sensor in relation to the vector of the Earth’s magnetic flux density
Complex Root Finding Algorithm Based on Delaunay Triangulation
- Piotr Kowalczyk
2015 Pełny tekst ACM TRANSACTIONS ON MATHEMATICAL SOFTWARE
A simple and flexible algorithm for finding zeros of a complex function is presented. An arbitrary-shaped search region can be considered and a very wide class of functions can be analyzed, including those containing singular points or even branch cuts. The proposed technique is based on sampling the function at nodes of a regular or a self-adaptive mesh and on the analysis of the function sign changes. As a result, a set of candidate points is created, where the signs of the real and imaginary parts of the function change simultaneously. To verify and refine the results, an iterative algorithm is applied. The validity of the presented technique is supported by the results obtained in numerical tests involving three different types of functions.
Compliance tests of the polymer layers used as hydrodynamic bearing coatings
- Michał Wasilczuk
- Michał Wodtke
2015
Operational experience and scientific investigations results showed that polymer lined hydrodynamic bearings can withstand more severe operating conditions compared than white metal bearings. PTFE and PEEK-based coatings are the most frequently used as Babbitt alternatives. Both polymers differ significantly from the each other in material properties. According to catalogue data compression modulus of PTFE, it is about an order of magnitude smaller compared to PEEK. This seems to have a significant influence on coating deflection (oil gap geometry) during bearing operation and as a consequence on bearing properties. Additionally, in order to bond polymer to pad steel body, it is necessary to apply intermediate layer, which also changes the stiffness of the bearing lining. In this work results of the compression tests of the samples cut out from a bearing pad are presented. Two types of material coatings were tested: PTFE-based and PEEKbased polymers. Tests were carried out for four temperatures varying from 25 to 120 oC. As a result, apparent compression modulus of the coatings as a function of temperature was evaluated. Results proved that both materials show significant differences in behaviour under compression.
Comprehensive compensation of grid current distortion by shunt active power filters
- Artur Cichowski
- Wojciech Śleszyński
- Janusz Nieznański
2015
The paper presents a comprehensive approach to the compensation of grid current distortion in shunt active power filter systems. Four sources of current distortion are addressed: imperfect grid synchronization caused by the distortion in the grid voltages, time delays in the evaluation of grid voltages and computation of compensating currents, fluctuations of the dc bus voltage, and the distortion of inverter output voltages due to deadtime effects and related factors. The focus of the paper is on the assessment of the significance of the proposed improvements in the control algorithm for the reduction of harmonic distortion of grid currents.
Comprehensive two-dimensional gas chromatography and three-dimensional fluorometry for detection of volatile and bioactive substances in some berries
- Tomasz Dymerski
- Jacek Namieśnik
- Kann Vearasilp
- Patricia Arancibia-Avila
- Fernando Toledo
- Elena Katrich
- Shela Gorinstein
2015 TALANTA.The International Journal of Pure and Applied Analytical Chemistry
The volatilefractionsofCapegooseberryandblueberryweredeterminedbyheadspacesolid-phase microextractioncoupledwithcomprehensivetwo-dimensionalgaschromatographywithtime-of-flight mass spectrometry(HS-SPME/GCGC-TOFMS).Thehighestamountofalcohol(51.8%),ester(32.8%)and carboxylicacid(6.9%)wasinblueberryincomparisonwithgooseberryandoppositelyketones(14.7%), aldehydes(9.9%)andterpenes(8%)werefoundingooseberry.Thebioactivecompoundsandantioxidant capacities werehigherinblueberriesthaningooseberries.Threedimensional fluorescenceemission spectrometry (3D-FL)wasappliedtodetermineandtocompareexperimentallyfoundbinding parametersofberriesextractswithhumanserumalbumin(HSA).The fluorescence quenchingofHSA by polyphenolsfromberrieswasaresultoftheformationofapolyphenol–HSA complex.Thebinding abilities ofberrieswerehighlycorrelatedwiththebioactivityofpolyphenolsandvolatilesubstances. The clusteranalysis(CA)andlineardiscriminantanalysis(LDA)wasappliedtodifferentiatetheberries samples accordingtotheirtype.
Computational complexity and length of recorded data for fluctuation enhanced sensing method in resistive gas sensors
- Łukasz Lentka
- Janusz Smulko
2015
This paper considers complexity and accuracy of data processing for gas detection using resistance fluctuation data observed in resistance gas sensors. A few selected methods were considered (Principal Component Analysis – PCA, Support Vector Machine – SVM). Functions like power spectral density or histogram were used to create input data vector for these algorithms from the observed resistance fluctuations. The presented considerations are important for proposing relatively cheap and mobile gas detection devices of limited computations abilities and utilizing fluctuation enhanced gas sensing method.
Computational simulations of concrete behaviour under dynamic conditions using elasto-visco-plastic model with non-local softening.
- Ireneusz Marzec
- Andrzej Tejchman-Konarzewski
- Andrzej Winnicki
2015 Computers and Concrete
W artykule przedstawiono wyniki obliczeniowych symulacji zachowania betonu w warunkach dynamicznych stosując sprężysto-lepko-plastyczny model z nielokalnym osłabieniem. Wykonano obliczenia dla ściskania jednoosiowego, rozciągania jednoosiowego i zginania. Dla dużych prędkości obciążenia uwzględniono fragmentację materiału. Wyniki porównano z doswiadczeniami.