Show publications from the year
-
Show all publications from the year 2025
-
Show all publications from the year 2024
-
Show all publications from the year 2023
-
Show all publications from the year 2022
-
Show all publications from the year 2021
-
Show all publications from the year 2020
-
Show all publications from the year 2019
-
Show all publications from the year 2018
-
Show all publications from the year 2017
-
Show all publications from the year 2016
-
Show all publications from the year 2015
-
Show all publications from the year 2014
-
Show all publications from the year 2013
-
Show all publications from the year 2012
-
Show all publications from the year 2011
-
Show all publications from the year 2010
-
Show all publications from the year 2009
-
Show all publications from the year 2008
-
Show all publications from the year 2007
-
Show all publications from the year 2006
-
Show all publications from the year 2005
-
Show all publications from the year 2004
-
Show all publications from the year 2003
-
Show all publications from the year 2002
-
Show all publications from the year 2001
-
Show all publications from the year 2000
-
Show all publications from the year 1999
-
Show all publications from the year 1998
-
Show all publications from the year 1988
-
Show all publications from the year 1987
-
Show all publications from the year 1980
Publications from the year 2018
Show all-
10 JAHRE LIGHT SYMPOSIUM WISMAR (LSW)
- Michael F. Rohde
- Karolina Zielińska-Dąbkowska
Die Zukunft von Licht und Beleuchtung stand im Mittelpunkt des international ausgerichteten Light Symposiums Wismar (LSW), das vom 4. bis 8. November 2008 im Rahmen des Festjahres zum hundertjährigen Bestehen der Hochschule Wismar an der Fakultät Gestaltung stattfand. Ein weitaus wichtigerer Grund war der Wunsch, das Thema Licht und Gesundheit ganzheitlich zu thematisieren. Licht, Raum und Ästhetik sollten in Kongruenz zum salutogentischen* Kontext von Gebäuden gesehen werden. Die bereits langjährige Partnerschaft der HSW (Hochschule Wismar) zur KTH Stockholm (Königliche Technische Hochschule) war Basis einer fruchtbaren, zusätzlichen Partnerschaft auf der Ebene der wissenschaftlichen Kooperation durch das Light Symposium. Von 2008 an sollte es alle 4 Jahre in Wismar, bzw. alternierend in Stockholm stattfinden. Somit ergab sich alle 2 Jahre ein aktueller, wissenschaftlicher Gedankenaustausch zum Thema »Licht, Gesundheit und Architekturbeleuchtung «. Zehn Jahre später wird in Stockholm das nächste Light Symposium (5.-7. Dezember 2018) ausgerichtet.
-
1D portable optical coherence tomography system
- Aleksandra MARIA Kamińska
- Marcin Strąkowski
—Imaging methods are an expanding branch of technology, which involves data acquisition and analysis of images for research and diagnostics. This paper has been devoted to the description of the optical design for a one-dimensional, portable optical coherence tomography (OCT) system. The Mach-Zehnder interferometer has been designed in the presented study. The description of the construction and applied hardware solutions have been presented. Moreover, dedicated software tools for signal processing and data acquisition have been developed.
-
3-D finite-difference time-domain modelling of ground penetrating radar for identification of rebars in complex reinforced concrete structures
- Jacek Lachowicz
- Magdalena Rucka
This paper presents numerical and experimental investigations to identify reinforcing bars using the ground penetrating radar (GPR) method. A novel element of the paper is the inspection of different arrangements of reinforcement bars. Two particular problems, i.e. detection of few adjacent transverse bars and detection of a longitudinal bar located over or under transverse reinforcement, have been raised. An attention was also paid to the influence of few adjacent bars on the estimation of wave velocity in concrete based on the diffraction hyperbola. The GPR simulations were undertaken using the finite-difference time-domain (FDTD) method. The new approach for the numerical modelling of GPR in complex reinforced concrete structures with the use of a 3-D FDTD model was presented. Simulated scans for the 3-D model were compared with results of in situ surveys. The results of investigations showed high usefulness of the 3-D model for the GPR field propagation in structures with a complex system of the reinforcement.
-
3D Model Preparing Patterns for Interactive Urban Visualization - Guidelines for Graphic Designers Preparing 3D Models for Virtual Reality Applications
- Dominik Pielak
- Mateusz Kowalski
- Jacek Lebiedź
While working on architectural visualizations, the software developer often has to work with graphic designers who create models in a different environment what can cause many complications. For this reason, it is very important to have some guidelines which can protect both the developer and the designer from commixing mistakes. The paper presents a list of such guidelines based on the authors’ experience. The reader can treat the paper as a first step in the development of a service based on cloud computing that verifies the correctness of graphical data in urban visualizations.
-
3D MODELLING OF CYLINDRICAL-SHAPED OBJECTS FROM LIDAR DATA - AN ASSESSMENT BASED ON THEORETICAL MODELLING AND EXPERIMENTAL DATA
- Katarzyna Bobkowska
- Artur Janowski
- Jakub Szulwic
Despite the increasing availability of measured laser scanning data and their widespread use, there is still the problem of rapid and correct numerical interpretation of results. This is due to the large number of observations that carry similar information. Therefore, it is necessary to extract from the results only the essential features of the modelled objects. Usually, it is based on a process using filtration, followed by simplification and generalization of redundant contents of datasets. This process must ensure the collection of new data without loss of information contained therein, the description accuracy of the key features of a measured object, as well as the uniqueness and comparability of results. In this paper, the authors extend the already extensive range of algorithms for the automatic or semiautomatic modelling of cylindrical objects, which have been measured using the laser scanning technology, with the one employing a concave hull or-in general-the alpha-shape (α-shape). The applicability of the proposed method was analysed using simulated data-generated analytically with the introduced and established systematic error with normal distribution-and using real results of the measurement of cylindrical-shaped objects. For real data, the obtained results were compared with the reference data. This made it possible to determine the validity of the proposed new method.
-
3D Object Shape Reconstruction from Underwater Multibeam Data and Over Ground Lidar Scanning
- Marek Kulawiak
- Zbigniew Łubniewski
The technologies of sonar and laser scanning are an efficient and widely used source of spatial information with regards to underwater and over ground environment respectively. The measurement data are usually available in the form of groups of separate points located irregularly in three-dimensional space, known as point clouds. This data model has known disadvantages, therefore in many applications a different form of representation, i.e. 3D surfaces composed of edges and facets, is preferred with respect to the terrain or seabed surface relief as well as various objects shape. In the paper, the authors propose a new approach to 3D shape reconstruction from both multibeam and LiDAR measurements. It is based on a multiple-step and to some extent adaptive process, in which the chosen set and sequence of particular stages may depend on a current type and characteristic features of the processed data. The processing scheme includes: 1) pre-processing which may include noise reduction, rasterization and pre-classification, 2) detection and separation of objects for dedicated processing (e.g. steep walls, masts), and 3) surface reconstruction in 3D by point cloud triangulation and with the aid of several dedicated procedures. The benefits of using the proposed methods, including algorithms for detecting various features and improving the regularity of the data structure, are presented and discussed. Several different shape reconstruction algorithms were tested in combination with the proposed data processing methods and the strengths and weaknesses of each algorithm were highlighted.
-
4D Models in World Wide Web
- Beata Hejmanowska
- Slawomir Mikrut
- Agnieszka Strus
- Ewa Glowienka
- Krystyna Michalowska
The paper presents some results of research curried out within the framework of the European project named "Cultural Heritage Through Time" (CHT2). One of the main project aims were to develop a methodology for sharing multi-temporal information via the Internet (webGIS) for remote analysis of structures and landscapes over time. Reported in this paper results are focused on testing two technologies (Hexagon and Esri) for online publication 3D models using as an example Fort Citadel 2 "Ko?ciuszko". The problems that were encountered and the examples of their solution are given. The main limitation in 4D web publishing is data volume and some simplification procedure should be involved.
-
5-Selenocyanato and 5-trifluoromethanesulfonyl derivatives of 2′-deoxyuridine: synthesis, radiation and computational chemistry as well as cytotoxicity
- Samanta Makurat
- Magdalena Zdrowowicz
- Lidia Chomicz-Mańka
- Witold Kozak
- Illia E. Serdiuk
- Paweł Wityk
- Alicja Kawecka
- Marta Sosnowska
- Janusz Rak
5-Selenocyanato-2′-deoxyuridine (SeCNdU) and 5-trifluoromethanesulfonyl-2′-deoxyuridine (OTfdU) have been synthesized and their structures have been confirmed with NMR and MS methods. Both compounds undergo dissociative electron attachment (DEA) when irradiated with X-rays in an aqueous solution containing a hydroxyl radical scavenger. The DEA yield of SeCNdU significantly exceeds that of 5-bromo-2′-deoxyuridine (BrdU), remaining in good agreement with the computationally revealed profile of electron-induced degradation. The radiolysis products indicate, in line with theoretical predictions, Se–CN bond dissociation as the main reaction channel. On the other hand, the DEA yield for OTfdU is slightly lower than the degradation yield measured for BrdU, despite the fact that the calculated driving force for the electron-induced OTfdU dissociation substantially overpasses the thermodynamic stimulus for BrdU degradation. Moreover, the calculated DEA profile suggests that the electron attachment induced formation of 5-hydroxy-2′-deoxyuridine (OHdU) from OTfdU, while 2′-deoxyuridine (dU) is mainly observed experimentally. We explained this discrepancy in terms of the increased acidity of OTfdU resulting in efficient deprotonation of the N3 atom, which brings about the domination of the OTfdU(N3–H)− anion in the equilibrium mixture. As a consequence, electron addition chiefly leads to the radical dianion, OTfdU(N3–H)˙2−, which easily protonates at the C5 site. As a result, the C5–O rather than O–S bond undergoes dissociation, leading to dU, observed experimentally. A negligible cytotoxicity of the studied compounds toward the MCF-7 cell line at the concentrations used for cell labelling calls for further studies aiming at the clinical use of the proposed derivatives.
-
9. Charytatywna aukcja sztuki współczesnej na rzecz dzieci z autyzmem Aperio
- Krzysztof Wróblewski
-
A Biofeedback System that Uses the Game to Study Electrical Muscle Activity
- Paweł Troka
- Hubert Toczko
- Piotr Przystup
- Mariusz Kaczmarek
The aim of this project was to design a system that will allow performing repetitive muscle exercises using a biofeedback device. It is supposed to enhance the motivation and attractiveness of the performed tasks thanks to an interactive game developed for mobile devices with the Android operating system. The built-in calibration mechanisms enable the users to play a game that is independent of their abilities which evens out the level of all players. The data in the form of EMG signal is gathered directly from the patient's body's surface in real-time and is sent wirelessly for further processing. While testing the system's efficiency, two types of calibration processes used in the mobile application were carried out.
-
A Broadband Circularly Polarized Wide-Slot Antenna with a Miniaturized Footprint
- Ubaid Ullah
- Sławomir Kozieł
This letter presents a novel and simple feeding technique for exciting orthogonal components in a wide-slot antenna. In this technique, a rectangular bracket-shape parasitic strip is placed at the open end of the straight microstrip line to excite the fundamental horizontal and vertical components of the circular polarization (CP). The proposed technique—when employed in conjunction with the asymmetrical geometry of coplanar waveguide (CPW) and a protruded stub from the ground plane—permits for maintaining axial ratio (AR) below 3 dB within a wide range in the C-band as well as a compact footprint of the antenna. All geometry parameters of the antenna are adjusted through rigorous EM-driven optimization to obtain the best performance in terms of footprint, impedance matching, and axial ratio bandwidth (ARBW). The size of the proposed antenna is only 27 mm × 28.8 mm. The structure features a 62 percent impedance bandwidth (3.6 GHz-6.85 GHz) and ARBW of approximately 49 percent (3.6 GHz to 5.93 GHz) with the average realized gain of 3.3 dB within the CP operating band. Numerical results are validated experimentally. Close agreement between simulation and measurement results has been observed.
-
A case study of odour nuisance evaluation in the context of integrated urban planning
- Joanna Badach
- Paulina Kolasińska
- Paciorek Małgorzata
- Wojciech Wojnowski
- Tomasz Dymerski
- Jacek Gębicki
- Małgorzata Dymnicka
- Jacek Namieśnik
Odour nuisance poses a serious problem in many urban areas, yet its evaluation and mitigation is often omitted in the urban planning process. By identifying its range and spatio-temporal variations, it could be taken into consideration by planners in urban development strategies and land use decisions. The aim of the study was to present the application of odour evaluation techniques in the improvement of the quality of life in the built environment. The problem of odours is discussed in regard to human health, social aspects and current practices in the management of spatial development. The application possibilities of field olfactometry are demonstrated based on a case study of a municipal landfill which is a major source of odour nuisance for the adjacent areas. The results of odour nuisance measurements were field olfactometry combined with topographical and meteorological data. Using dispersion modelling (non-steady-state Lagrangian Gaussian puff model CALPUFF with dedicated meteorological pre-processor CALMET) it was possible to calculate odour concentrations and to place the measured odour concentrations in a specific spatial context. The obtained results were juxtaposed with local development strategies and discussed in the context of environmental-based planning. We suggest that odour evaluation and dispersion modelling are valid tools in managing the dynamics of urban growth.
-
A Compact Basis for Reliable Fast Frequency Sweep via the Reduced-Basis Method
- Valentin de la Rubia
- Michał Mrozowski
A reliable reduced-order model (ROM) for fast frequency sweep in time-harmonic Maxwell’s equations by means of the reduced-basis method is detailed. Taking frequency as a parameter, the electromagnetic field in microwave circuits does not arbitrarily vary as frequency changes, but evolves on a very low-dimensional manifold. Approximating this low-dimensional manifold by a low dimension subspace, namely, reduced-basis space, gives rise to an ROM for fast frequency sweep in microwave circuits. This avoids carrying out time-consuming finite-element analysis for each frequency in the band of interest. The behavior of the solutions to Maxwell’s equations as a function of the frequency parameter is studied and highlighted. As a result, a compact reduced-basis space for efficient model-order reduction is proposed. In this paper, the reduced-basis space is composed of two parts: 1) eigenmodes hit in the frequency band of interest, which form an orthogonal, fundamental set that describes the natural oscillating dynamics of the electromagnetic field and 2) whatever else electromagnetic fields, sampled in the frequency band of interest, that are needed to achieve convergence in the reduced-basis approximation. The reduced-basis method aims not only to find out a reduced-basis space in an efficient way, but also to certify the reliability of the approximation carried out. Emphasis is placed on a fast evaluation of the ROM error measure and on providing a reliable convergence criterion. This approach is applied to both narrowband resonating structures and wideband nonresonanting devices in order to show the capabilities of the method in real-life applications.
-
A comparative analysis of the effectiveness of corporate bankruptcy prediction models based on financial ratios: Evidence from Colombia, 2008 to 2015
- Jackson Arroyave Jimenez
Logit and discriminant analyses have been used for corporate bankruptcy prediction in several studies since the last century. In recent years there have been dozens of studies comparing the several models available, including the ones mentioned above and also probit, artificial neural networks, support vector machines, among others. For the first time for Colombia, this paper presents a comparative analysis of the effectiveness of several models predicting corporate bankruptcy. Such models have previously been mostly used in relation to European and North American markets, whereas here they are applied to the financial ratios of three firms located in Colombia. The main objective is to corroborate the validity of these models in terms of their ability to predict firm failure in the Latin American context, specifically for two bankrupt Colombian firms and one healthy one. The analysis is conducted using bankruptcy forecasting models widely proposed in the literature and used systematically in developed countries: the multiple discriminant analysis Z-Altman model, Korol’s two-function model and Prusak’s P2 model. In addition, the logit and decision tree models developed by T. Korol are tested.
-
A comparative study of English viseme recognition methods and algorithm
- Dawid Jachimski
- Andrzej Czyżewski
An elementary visual unit – the viseme is concerned in the paper in the context of preparing the feature vector as a main visual input component of Audio-Visual Speech Recognition systems. The aim of the presented research is a review of various approaches to the problem, the implementation of algorithms proposed in the literature and a comparative research on their effectiveness. In the course of the study an optimal feature vector construction and an appropriate selection of the classifier were sought. The experimental research was conducted on the basis of a spoken corpus in which speech was represented both acoustically and visually. The extracted features represented three types: geometrical, textural and mixed ones. The features were processed employing the classification algorithms based on Hidden Markov Models and Sequential Minimal Optimization. Tests were carried out employing the processed video material recorded with English native speakers who read specially prepared list of commands. The obtained results are discussed in the paper.
-
A comparative study of English viseme recognition methods and algorithms
- Dawid Jachimski
- Andrzej Czyżewski
- Tomasz Ciszewski
An elementary visual unit – the viseme is concerned in the paper in the context of preparing the feature vector as a main visual input component of Audio-Visual Speech Recognition systems. The aim of the presented research is a review of various approaches to the problem, the implementation of algorithms proposed in the literature and a comparative research on their effectiveness. In the course of the study an optimal feature vector construction and an appropriate selection of the classifier were sought. The experimental research was conducted on the basis of a spoken corpus in which speech was represented both acoustically and visually. The extracted features represented three types: geometrical, textural and mixed ones. The features were processed employing the classification algorithms based on Hidden Markov Models and Sequential Minimal Optimization. Tests were carried out employing the processed video material recorded with English native speakers who read specially prepared list of commands. The obtained results are discussed in the paper.
-
A Comparison of STI Measured by Direct and Indirect Methods for Interiors Coupled with Sound Reinforcement Systems
- Józef Kotus
- Bożena Kostek
- Adam Kurowski
- Piotr Szczuko
This paper presents a comparison of STI (Speech Transmission Index) coefficient measurement results carried out by direct and indirect methods. First, acoustic parameters important in the context of public address and sound reinforcement systems are recalled. A measurement methodology is presented that employs various test signals to determine impulse responses. The process of evaluating sound system performance, signals enabling direct objective measurement of the STI (Speech Transmission Index) coefficient, and in particular the STI-PA (STI for Public Address systems) ratio, are employed in accordance with the measurement standards. Sound systems installed in two acoustic interiors are used in the measurements. A comparison of the results obtained for different length of swept sine stimuli is made that enabled to recommend this test signal as more suitable for interiors coupled with sound reinforcement systems.
-
A comparison of structural and luminescence properties of lead(II) coordination polymers with isomeric thiophenecarboxylate ligands
- Mateusz Kowalik
- Joanna Masternak
- Katarzyna Kazimierczuk
- Bogumiła Kupcewicz
- Oleksiy Khavryuchenko
- Barbara Barszcz
Two new lead(II) coordination polymers with isomeric thiophenecarboxylates, namely [Pb(2tpCOO)2]n (1) and [Pb(3tpCOO)2(H2O)]n (2) (2tpCOO− = thiophene-2-carboxylate, 3tpCOO− = thiophene-3-carboxylate), were synthesized and characterized. Single crystal X-ray crystallography revealed a distorted pentagonal pyramidal geometry {PbO6} around Pb in 1 and a distorted dodecahedral geometry {PbO8} in 2. The distortion derived from the presence of 6 s2 inert electron pair on lead(II), which was confirmed by DFT calculations. The topological classification of obtained polymers has been performed, disclosing the SP 1-periodic net (4,4)(0,2) and gek1 topology in 1 and 2, respectively. Interactions stabilising crystal structures were also confirmed by Hirshfeld surface analysis. Fluorescence properties allowed to distinguish the type of thiophene-monocarboxylic acid isomers. The luminescence intensity which derived from π → π∗ and/or n → π∗ transitions is higher in 2tpCOOH. Photoluminescent properties of complexes 1 and 2 are much more enhanced in comparison to starting ligands. The emission bands in the complexes can be attributed to the ligand-to-metal charge transfer (LMCT) as a change in the intraligand transitions. Additional low energy emissions with large Stokes shifts appeared and were assigned to the metal-centered (MC) transitions involving s and p lead(II) orbitals, which were also confirmed by DFT calculations. Moreover, both complexes were characterized by infrared spectroscopy and thermal stability analysis.
-
A concept for reducing PM 10 emissions for car brakes by 50%
- Guido Perricone
- Vlastimil Matějka
- Mattia Alemani
- Giorgio Valota
- Andrea Bonfanti
- Alessandro Ciotti
- Ulf Olofsson
- Anders Söderberg
- Jens Wahlström
- Oleksii Nosko
- Giovanni Straffelini
- Stefano Gialanella
- Metinoz Ibrahim
With regard to airborne particles with an aerodynamic diameter of less than 10 μm (PM10), in countries in the European Union, the mass of brake emissions equals approximately 8–27% of the total traffic-related emissions. Using a research methodology combining tests at different scale levels with contact mechanics simulations and PM10 chemical characterization, the REBRAKE EU-financed project had the following aims: i) to demonstrate the possibility of reducing the PM10 fraction of the airborne particulate from brake wear by 50 wt%; ii) to enhance the general understanding on the physical and chemical phenomena underlying the brake wear process. The results achieved so far indicate that it is possible to design a disc brake system for a European standard car affording at least a 32 wt% PM10 emission reduction using a standard European pad and a heat-treated rotor. A further reduction to 65 wt% PM10 emission could be achieved with NAO pad material and the same heat-treated disc.
-
A CONCEPT OF DETERMINING THE RELATION BETWEEN LOAD AND WEAR OF TRIBOLOGICAL SYSTEMS OF SHIP MAIN SELF-IGNITION ENGINES BY USING PROBABILISTIC APPROACH PROBABILISTIC APPROACH
- Jerzy Girtler
This paper presents a proposal of simultaneous consideration of load and wear associated with it , of tribological systems of ship main engines (intended for ship propulsion) . Based on results of investigations it was assumed that both the load Q (i.e. a cause of wear ) and the wear Z (i.e. an effect of load occurrence) considered in a given time t(0 ≤ t ≤ t) are random variables Qt and Zt, respectively. There was characterized operational principle of ship main engines in definite external conditions (WZ) as well as consequences of excessive load of engines. Three hypotheses highlighting relations existing between load and wear of the above mentioned systems, have been proposed. The first of them deals with explanation of stochastic relation between load and wear, the second highlights why it is possible to assume that the load Qt and the wear Zt are positively correlated , and the third – why it is possible to assume that coefficient of correlation between Qt and Zt may be taken close to one.