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Publications from the year 2017
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1,3,4-Thiadiazole-based diamides: Synthesis and complexation properties
- Natalia Łukasik
- Elżbieta Luboch
- Jarosław Chojnacki
- Ewa Wagner-Wysiecka
Aromatic diamides, derivative of 2,6-pyridinedicarboxylic acid and isophthalic acid, bearing 1,3,4-thiadiazole residue were prepared with satisfactory yields in conventional procedures and microwave stimulated reactions. X-ray structure of N,N-bis (1,3,4-thiadiazol-2-yl)-2,6-pyridinedicarboxamide (2) DMSO solvate (2DMSO) was described. Selective zinc(II), lanthanum(III), terbium(III) and L-tyrosine recognition was found for N,N-bis(1,3,4-thiadiazol-2-yl)-2,6-pyridinedicarboxamide in DMSO and its mixture with water. The IDA (Indicator Displacement Assay) system for metal cations sensing was proposed. The binding properties of 2 were compared with newly synthesized N,N-bis(1,3,4-thiadiazol-2-yl)-1,3-benzenedicarboxamide 1.
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20+ years of Polish residential real estate prices – a house price index proxy
- Błażej Kochański
Information on house prices is often considered crucial when assessing developments in economy. However, in Poland for the long time house prices haven’t been tracked in an organized manner. Recent developments, most notably house price indices developed by Poland’s national bank and by the statistical office do not go back more than 10 years, therefore data series are relatively short compared to those of other macroeconomic data. In the paper a collection of publicly available data on Polish house prices from various sources is presented. House price index estimate is then proposed which goes back to 1995 and covers periods of housing boom and the financial crisis. The index should be treated as a proxy due to the fact that the data availability is limited and the source data are based on various, sometimes not clearly articulated, methodologies. Nevertheless this proxy index may prove useful as – to the knowledge of the author – there has been no other publicly available attempt at reconstructing the latest history of residential real-estate prices in Poland. Furthermore, some researchers used to take inadequate data, like residential construction cost, as a proxy for house prices, which may have led to wrong conclusions. The index may be further improved when new data emerge on history of house prices before 2006 and more advanced methodologies are used.
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3-Acyloketeny generowane z 5-acylo-2,2-dimetylo-1,3-dioksa-4,6-dionów w syntezie mono i bicyklicznych układów β-laktamowych
- Anna Zakaszewska
Zakres rozprawy obejmuje dwa zróżnicowane tematycznie zagadnienia. Zasadniczy fragment opisuje próby stereoselektywnej syntezy układów β-laktamowych na drodze cykloaddycji ketenów generowanych termicznie z pochodnych kwasu Meldruma z iminami. Pozostałą część badań stanowi wątek cyklizacji metatetycznych. Zagadnienie stereoselektywnej syntezy β-laktamów w wyniku cykloaddycji aldimin do generowanych termicznie z rozkładu pochodnych kwasu Medruma ketenów dobrze wpisuje się w jeden z intensywnie rozwijanych nurtów badawczych syntetycznej chemii organicznej. Dotyczy niezbadanego dotychczas obszaru reaktywności kwasu Meldruma, który to związek był wcześniej wielokrotnie analizowany w naszym zespole. Kluczowym ogniwem badań własnych są reakcje stereoselektywnej [2+2] cykloaddycji imin zawierających centrum asymetrii w części aminowej do ketenów generowanych z 5-podstawionych pochodnych kwasu Meldruma. Rozległe badania nad wpływem struktury substratów i warunków prowadzenia reakcji pozwoliły uzyskać ciekawe wnioski odnośnie reaktywności i rozszerzyć prowadzone eksperymenty o tematykę cyklizacji metatetycznych produktów cykloaddycji imin do ketenów. Konsekwencją uzyskanych wyników są też interesujące spostrzeżenia na temat mechanizmu reakcji tworzenia β-laktamów.
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3D Printing of Metallic Implants
- Tomasz Seramak
- Katarzyna Zasińska
- Andrzej Zieliński
- Michał Gubański
The fabrication of various elements, solid and open porous structures of stainless steel and Ti alloy is described. The process was started with the design of 3D models in CAD/CAM system. The 3D models were transformed into *.stl files and then the manufacturing process of the real structures by means of the selective laser melting with the SLM Realizer 100 3D printer was made. The paper shows the porous specimens made for possible application in medicine and the prosthetic bridges. The appropriate mechanical strength is the important property of porous structures for medical application and for curved prosthetic bridges it is necessary to take into account the thermal stresses, which appear during their SLM/DMLS manufacturing process.
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A body position influence on ECG derived respiration
- Piotr Przystup
- Artur Poliński
- Adam Bujnowski
- Tomasz Kocejko
- Jerzy Wtorek
An influence of a human body position on ECG derived respiration (EDR) signal is presented in the paper. Examinations were performed during deep, suspended and normal breathing for eight people in four different body positions. EDR and thoracic impedance signals were compared using correlation and standard deviation coefficients. Obtained results have shown that it is possible to monitor breath activity of people being in different position, however a precise interpretation of the obtained signal is limited.
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A CMOS Pixel With Embedded ADC, Digital CDS and Gain Correction Capability for Massively Parallel Imaging Array
- Miron Kłosowski
- Waldemar Jendernalik
- Jacek Jakusz
- Grzegorz Blakiewicz
- Stanisław Szczepański
In the paper, a CMOS pixel has been proposed for imaging arrays with massively parallel image acquisition and simultaneous compensation of dark signal nonuniformity (DSNU) as well as photoresponse nonuniformity (PRNU). In our solution the pixel contains all necessary functional blocks: a photosensor and an analog-to-digital converter (ADC) with built-in correlated double sampling (CDS) integrated together. It is implemented in standard 0.18 μm CMOS technology. The size of the pixel with 9-bit resolution is 21 μm x 21 μm. Measurements of the 128 x 128 pixel array confirm functionality of the proposed solution. CDS reduces dark FPN from 12 LSB (3%) to 0.8 LSB (0.2%) and light FPN from 14 LSB (3.7%) to 7 LSB (1.8%). Further reduction of the light FPN (to ~1 LSB) was achieved by compensating PRNU using massively parallel innovative digital multiplication which features good resolution (1/511), does not disturb CDS executed at the same time, and can be implemented within a small pixel area.
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A compact smart sensor based on a neural classifier for objects modeled by Beaunier's model
- Zbigniew Czaja
- Michał Kowalewski
A new solution of a smart microcontroller sensor based on a simple direct sensor-microcontroller interface for technical objects modeled by two-terminal networks and by the Beaunier’s model of anticorrosion coating is proposed. The tested object is stimulated by a square pulse and its time voltage response is sampled four times by the internal ADC of microcontroller. A neural classifier based on measurement data classifies the tested object to a given degradation stage.
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A comparative study on selective properties of Kraft lignin–natural rubber composites containing different plasticizers
- Janusz Datta
- Paulina Parcheta
Effect of plasticizer type on the kraft lignin–nat- ural rubber composite microstructure and selected proper- ties was determined. The composites were prepared with addition of a commonly used naphthenic oil plasticizer to study the decomposition product of polyurethane (glyc- erolysate) and its characteristics. Kraft lignin powder was incorporated into the natural rubber matrix in amounts of 10 and 40 parts per 100 parts of natural rubber (phr). The reference samples were prepared without any lignin pre- sent. The chemical interaction between the filler particles and natural rubber macromolecules was analyzed by Fou- rier transform infrared spectroscopy (FTIR) and the adhe- sion was characterized by scanning electron microscopy (SEM). The results of the adhesion measurements con- firmed poor distribution of lignin particles into the natural rubber matrix with increasing filler content. Optimal lignin content in the composites was 10 phr in the case of both plasticizers. Moreover, the results of FTIR verified the for- mation of non-covalent bonds and the need for modifica- tion of the filler to enhance the reinforcing effect in the nat- ural rubber matrix. Dynamic mechanical analysis (DMA) and mechanical measurements proved that the specimen containing 10 phr of lignin with the use of glycerolysate as plasticizer displayed the highest mechanical performance. It was demonstrated that glycerolysate and naphthenic oil as plasticizing agents showed similar effect on the thermal properties of the prepared composites. Also, the measured mechanical properties, such as tensile strength, hardness, resilience, and abrasiveness confirmed these findings
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A Comparison of Simplified Two-dimensional Flow Models Exemplified by Water Flow in a Cavern
- Dzmitry Prybytak
- Piotr Zima
The paper shows the results of a comparison of simplified models describing a two-dimensional water flow in the example of a water flow through a straight channel sector with a cavern. The following models were tested: the two-dimensional potential flow model, the Stokes model and the Navier-Stokes model. In order to solve the first two, the boundary element method was employed, whereas to solve the Navier-Stokes equations, the open-source code library OpenFOAM was applied. The results of numerical solutions were compared with the results of measurements carried out on a test stand in a hydraulic laboratory. The measurements were taken with an ADV probe (Acoustic Doppler Velocimeter). Finally, differences between the results obtained from the mathematical models and the results of laboratory measurements were analysed.
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A Comparison of the Efficiency of Deammonification under Different Aeration Strategies in a Laboratory-Scale Sequencing Batch Reactor
- Hussein Al-Hazmi
- Joanna Majtacz
- Przemysław Kowal
- Yan Feng
- Jacek Mąkinia
An important source of nitrogen load entering the biological part of wastewater treatment plants (WWPTs) is derived from the anaerobic sludge digestion processes. Sludge digestion liquors constitute only 1-2% of the inflow to the plant, but the load of nitrogen directed with them to the main stream may be as high as 10-20% of the total nitrogen load. Therefore, numerous studies have focused on treatment of sludge digestion liquors using alternative methods to the conventional nitrification-denitrification. In particular, the deammonification process is very promising and may constitute the successful strategy for nitrogen removal (Shaughnessy et al., 2011). The deammonification process involves two steps. The first step is the partial nitrification of ammonia (NH4-N) by ammonia oxidizing bacteria (AOB) to produce nitrite (NO2-N) and the second step is the anammox process to “anaerobically” oxidize ammonia to nitrogen gas with nitrite as an electron acceptor (Lackner et al., 2014). The aim of this study was to examine the impact of dissolved oxygen (DO) concentration and selected aeration strategy on enhancing the deamonification process. A special attention has been paid to testing and comparing the process performance at the different aeration strategies, i.e. intermittent aeration vs. continuous aeration.
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A Concept of Freight Traffic Flow Regulations in the City of Gdansk
- Daniel Kaszubowski
- Filip Heleniak
This paper presents a review of state-of-art efforts in urban freight transport modelling in the context of their requirements and applicability as a basis for evaluation of city's freight transport policy. Freight transport mirrors all aspects of the city's economic activity and for that reason its proper planning is of extreme importance. However, urban freight system may be considered as the most varied and fragmented element of urban transport system. To address this challenge reliable planning framework is required for analysis and implementation of any measure oriented at increase of efficiency of urban freight transport system. Thus, the main goal of this paper is to verify the main characteristics of recent urban freight models with regards to current maturity of freight planning system. The case of Gdynia has been selected because the city has adopted a Sustainable Urban Mobility Plan in October 2016. The Plan includes several measures related to management of urban freight and distribution system. Available urban freight models have been verified according to 1) stakeholders involved in the model, 2) the descriptor for modelling purpose, 3) the objective of the model and 4) the solution approach implemented for achieving the objective. Urban freight measures included in the Gdynia's SUMP has been confronted with this framework to find the gaps in modelling requirements, i.e. data needs versus data already available. The results show that an extensive effort is required to achieve competence level which would allow to introduce selected mesures. One of the main problems identified within a context of urban freight modelling is mismatching of scarce available data to even basic analysis of transport processes. Without reliable picture of existing situation any progress towards freight measures evaluation and planning would be futile. However, there are first examples of change on this field. One is URBACT FreightTails project where delivery profile at selected streets in Gdynia will be developed.
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A concept of heterogeneous numerical model of concrete for GPR simulations
- Jacek Lachowicz
- Magdalena Rucka
The Ground Penetrating Radar (GPR) method, which is increasingly being used in the non-destructive diagnostics of reinforced concrete structures, often needs more accurate interpretation tools for analysis of experimental data. Recently, there has been growing interest in developing of various numerical models for exhaustive understanding of GPR data. This paper presents the concept of a heterogeneous numerical model of concrete, in which individual components of concrete are separate materials and their location in the model is pseudo-random. The numerical model was validated with the Complex Refractive Index Model (CRIM). In addition, experimental surveys were conducted on a reinforced concrete footbridge with high saturation of water. Experimental radargrams were compared with numerical GPR maps, calculated using both homogeneous and heterogeneous models of concrete.
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A derivatisation agent selection guide
- Marek Tobiszewski
- Jacek Namieśnik
- Francisco Pena-Pereira
The development of new tools for providing high quality information in a cost-effective and expeditious way is one of the main aims of analytical chemistry. Remarkably, the introduc- tion of the 12 principles of green chemistry paved the way forward for the development of analytical methodologies that are, ideally, inherently safe for the operator and the environ- ment, with the least possible consumption of energy and chemicals, and minimum generation of wastes. Thus, green aspects are increasingly being considered besides the main features of analytical methods such as accuracy, sensitivity, selectivity and precision. In this way, both “3R” (reduction, re-placement and recycling) and “4S” (specific methods, smaller dimensions, simpler methods and statistics) approaches have been reported in the literature towards greener analytical methodologies.
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A DISCRETE-CONTINUOUS METHOD OF MECHANICAL SYSTEM MODELLING
- Rafał Hein
The paper describes a discrete-continuous method of dynamic system modelling. The presented approach is hybrid in its nature, as it combines the advantages of spatial discretization methods with those of continuous system modelling methods. In the proposed method, a three-dimensional system is discretised in two directions only, with the third direction remaining continuous. The thus obtained discrete-continuous model is described by a set of coupled partial differential equations, derived using the rigid finite element method (RFEM). For this purpose, firstly the general differential equations are written. Then these equations are converted into difference equations. The derived equations, expressed in matrix form, allow to create a global matrix for the whole system. They are solved using the distributed transfer function method. The proposed approach is illustrated with the examples of a simple beam fixed at both ends and a simply supported plate.
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A distributed system for conducting chess games in parallel
- Aleksander Rydzewski
- Paweł Czarnul
This paper proposes a distributed and scalable cloud based system designed to play chess games in parallel. Games can be played between chess engines alone or between clusters created by combined chess engines. The system has a built-in mechanism that compares engines, based on Elo ranking which finally presents the strength of each tested approach. If an approach needs more computational power, the design of the system allows it to scale. The system was designed using a loosely coupled architecture approach and the master-slave pattern. It works under Unix or MacOS operating systems. In order to split chess engine processing between every CPU in the system the Akka technology with the Scala language was used while the other part was written in Java. We tested many free chess engines connected to the system by the UCI protocol supported by the proposed system. CloudAMQP is an implementation of Advanced Message Queue Protocol and was used as a message-oriented middleware. This layer was created to split games between every available processing node connected to the system. This element also contributes to greater fault tolerance. We present results of games played between many available chess engines.
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A DSC and NMR-Relaxation study of the molecular mobility of water protons interacting with chemically modified starches
- A.i. Sergeev
- N.g. Shilkina
- L.a Wasserman
- S.i. Shilov
- Hanna Staroszczyk
Changes in the mobility of water protons in the chemically modified starches (CMS)–water system are studied by differential scanning calorimetry and NMR relaxation. The amounts of unfrozen water at negative temperatures and additional (after gelation) unfrozen for CMS are lower than those for native starch. The proton spin–spin relaxation time T2 for CMS samples, conventionally attributed to the water fraction in starch granules, decreases monotonically with increasing temperature, whereas for native starch, this dependence exhibits an extreme behavior. Studying the dispersion dependences for 7 wt % gels, which characterize the rate of chemical exchange of water protons with protons of hydroxyl groups of polysaccharides, showed the absence of this kind of dependence for the CMS studied when the instrument operated at a frequency of 20 MHz. This data indicate the significant destructive changes in the structure of the CMS.
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A fast procedure of stress state evaluation in magnetically anisotropic steels with the help of a probe with adjustable magnetizing field direction
- Marek Chmielewski
- Leszek Piotrowski
- Bolesław Augustyniak
The paper presents a novel approach to the stress state evaluation issue. It deals with a strongly (magnetically) anisotropic materials for which a direct interpretation of the Barkhausen effect (BE) intensity would lead to erroneous results. In such a case one has to take into account both the measured BE intensity and the orientation of the magnetisation direction relative to the magnetic easy axis. For the in plane stress distribution evaluation one has to perform at least three measurements in the non-collinear directions. The application of an apparatus with automatically changing magnetizing field direction allows to obtain the angular distribution of the BE intensity in about 30 s (with the angular step of 10°). Thanks to the dedicated post-processing software the procedure of the measurement data processing, resulting in the full information on the stress distribution (main stress components and their orientation in all the investigated points) is almost instantaneous. Apart from the measurement results the stress determination procedure requires two additional pieces of information. The first one is the calibration data obtained for at least two applied strain directions (along easy and hard magnetisation axes)— the data for the intermediate orientations are usually interpolated. The second one is the ‘reference level’ of the BE intensity angular distribution. In the case of welded plates it is obtained by averaging the results obtained at the analysed points before welding. The way of results presentation proposed in that paper is very illustrative and shows an interesting feature of the stress distribution in welded plates—namely the appearance of a ‘vortex’ structure of main stress.
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A Framework of a Ship Domain-based Collision Alert System
- Rafał Szłapczyński
- Joanna Szłapczyńska
The paper presents a framework of a planned ship collision alert system. The envisaged system is compliant with IMO Resolution MSC.252 (83) “Adoption of the revised performance standards for Integrated Navigation Systems (INS)”. It is based on a ship domain-oriented approach to collision risk and introduces a policy of alerts on dangerous situations. The alerts will include cautions, warnings and alarms, which will be triggered by predicted violation of a ship domain or predicted passage in the domain’s proximity. The paper includes a description of the policy of alerts and examples of generating them for potentially threatening situations.
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A heterogenous wireless system for maritime communication - the netBaltic system architecture
- Michał Hoeft
- Krzysztof Gierłowski
- Krzysztof Bronk
- Adam Lipka
- Rafal Niski
- Krzysztof Zurek
In the article, the concept of a heterogeneous wireless maritime mesh network offering transmission for e.g., e-navigation services is presented. The constrains of existing and competitive solutions are discussed showing the need for a new system. The authors present detailed information about a netBaltic node's architecture and networking mechanisms offering different transmission capabilities and proposed for use on different sea areas. Moreover, the results of the performed measurements campaigns are presented to estimate operational ranges of the described system and its ability to meet the requirements of e-navigation services. Practical advantages of presented solutions are highlighted bringing out new possibilities in e-navigation.