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 2017
Show all-
Evaluation of citric acid corrosion inhibition efficiency and passivation kinetics for aluminium alloys in alkaline media by means of dynamic impedance monitoring
- Joanna Wysocka
- Stefan Krakowiak
- Jacek Ryl
A novel approach is proposed for constructing the adsorption isotherm in corrosion studies, based on a well-known interaction between citric acid and aluminium in alkaline electrolytes. Our approach utilizes the instantaneous impedance measurements via Dynamic Electrochemical Impedance Spectroscopy in galvanostatic mode (g-DEIS). Unlike other common tools, g-DEIS delivers exact information about the concentration required for full surface coverage with adsorbed inhibitor. A significantly larger data set enables observation of multi-stage mechanism of adsorption and complex interaction between citric acid and the metal surface. The obtained impedance results displayed a high convergence with other electrochemical, XPS and SEM studies carried out for verification purposes. It was shown that citric acid exhibits critical concentration with respect to the inhibition efficiency. Chemistry of the adsorbed layer was altered and secondary increase in the corrosion rate was observed in the excess of citric acid, a feature typical for surfactants. Furthermore, authors compared different aluminium alloys with respect to their corrosion resistance mediated by citric acid. The conclusion was reached that regardless of corrosion resistance, the kinetics and mechanism of passive layer formation in Al alloys depends only slightly on alloying additives. AA7020 alloy was an exception because of a specific interaction between zinc and citric acid.
-
Evaluation of Connectivity Gaps Impact on TCP Transmissions in Maritime Communications
- Michał Hoeft
- Józef Woźniak
Many organizations and research working groups, including among others IEEE, ITU, ETSI and IMO are currently working towards improvements in communication of different types of vehicles (cars, trains, planes and vessels) and upgrading utilities and services offered to their crews and passengers travelling all over the world. The paper deals with selected aspects of the TCP protocol connectivity in maritime wireless networks. The authors show results of measurements performed in a real-world maritime environment consisting of on- and off-shore devices and transmission systems, partly located on vessels. Based on the collected measurements, the authors provide statistical analysis, including connectivity periods and connectivity gaps observed as a result of vessels motions. The obtained statistical results were used, in turn, in a simulation test-bed to verify efficiency of TCP connections, assuming the use of Reno algorithm, together with F-RTO enhancement (Forward RTO-Recovery), Cubic algorithm, and further adjustments proposed by the authors. The results show significant increase of the average throughput (up to 3 times) and decrease of the average download time (up to 53%), as compared to the pure Reno TCP solution. The proposed modifications seem to be especially important and attractive for highly unreliable wireless links - expected to be very common in a maritime environment.
-
Evaluation of expanded uncertainty of instantaneous power measurement in a bearing diagnostic system.
- Ariel Dzwonkowski
The paper presents the issues concerning the estimation of the expanded uncertainty in the system for the diagnosis of rolling bearings, consisting of transducers: voltage and current voltage, which is used for diagnostic bearing motors method based on the measurement and analysis of the instantaneous power signal consumed by the induction motor. It presents the methodology for assessing the measurement uncertainty and presents examples of the results of analyses. On this basis, conclusions were drawn regarding the accuracy of the measurement system designed to diagnose bearings of induction motors by analysis of instantaneous power.
-
Evaluation of Face Detection Algorithms for the Bank Client Identity Verification
- Maciej Szczodrak
- Andrzej Czyżewski
Results of investigation of face detection algorithms efficiency in the banking client visual verification system are presented. The video recordings were made in real conditions met in three bank operating outlets employing a miniature industrial USB camera. The aim of the experiments was to check the practical usability of the face detection method in the biometric bank client verification system. The main assumption was to provide a simplified as much as possible user interaction with the application. Applied algorithms for face detection are described and achieved results of face detection in the real bank environment conditions are presented. Practical limitations of the application based on encountered problems are discussed.
-
Evaluation of foundation input motions based on kinematic interaction models
- Tomasz Falborski
The present study was designed to demonstrate the importance of base-slab averaging and embedment effects on the foundation-level input motions due to earthquake excitations. Evaluation of foundation-level input motions based on the most commonly adopted kinematic interaction models are presented. In order to conduct this investigation, original records of horizontal accelerations for two case-study buildings were utilized. Computed foundation-level input motions, in both NS and EW directions, were compared to the actual acceleration-time histories recorded at the foundation levels. The results clearly indicate that incorporating base-slab averaging and embedment effects in seismic analyses can modify the dynamic excitation imposed at the foundation level, and, as a consequence, lead to more accurate structural response due to earthquake ground motions.
-
Evaluation of Gas Chromatography Stationary Phases Based on Morpholinium Ionic Liquids by McReynolds Constants and Activity Coefficients at Infinite Dilution
- Kateryna Yavir
- Łukasz Marcinkowski
- Adam Kloskowski
- Jacek Namieśnik
In this work, four ionic liquids (ILs) based on the N-alkyl-N-methylmorpholinium cation ([Mor1,R], in which R = 2, 4, 8, or 10) and bis (trifluoromethanesulfonyl)imide anion were synthesized. Using GLC, a number of parameters describing the sorption properties of the investigated ILs were determined. The values of Kovats indices, McReynolds constants, and activity coefficients at infinite dilution were the basis for the evaluation of intermolecular interactions. The effect of the chain length of the alkyl substituent in the cation, which was used to modify their polarity, has been discussed. Comparison of the characteristics of the investigated IL-based stationary phases with commercially available ones allowed for the statement that the investigated ILs were more polar. The tested ILs had a relatively high polarity. Increasing the length of the alkyl chain in the morpholinium ring reduced polarity. ILs based on the morpholinium cation were tunable in a wide range of their polarity.
-
Evaluation of Low Temperature Properties of Rubberized Asphalt Mixtures
- Marek Pszczoła
- Mariusz Jaczewski
- Cezary Szydłowski
- Józef Judycki
- Bohdan Dołżycki
The paper presents low-temperature test results of asphalt mixtures designed with use of bitumen modified by crumb rubber and also SBS polymer. Laboratory tests were conducted on two types of asphalt mixtures for wearing course – stone matrix asphalt (SMA 8) and porous asphalt (PA 8). This paper presents results of the following laboratory tests at low temperatures: TSRST test, three point bending creep test, fracture toughness test and assessment of physical hardening. It was found that test results of asphalt mixtures with use of polymer-rubber modified bitumen showed high resistance to low temperature cracking in all tests conducted. In some cases use of polymer-rubber modified bitumen even increased resistance to low temperature cracking in comparison with standard SBS polymer modified bitumen. The additional advantage is that usage of crumb rubber allows to reduce the amount of added polymers with respect to the standard SBS polymer modified bitumen.
-
Evaluation of open drone map toolkit for geodetic grade aerial drone mapping – case study
- Paweł Burdziakowski
An open source tool’s popularity has increased considerably, as well as micro aerial vehicles (MAV) technologies based on open source hardware. An open source software and hardware delivers a wide variety of applications and technology. The world’s most successful open source projects have their roots in the academy, and now its participation includes a wide variety of academic programs and research. Based on open source technology, a case study has been designed and performed, in order to prove this technology meets geodetic requirements. The study has been performed within tested area, using MAV with construction and design based only on open hardware technology. All image data gathered have been post processed using recently developed open source toolkit for aerial drone mapping – Open Drone Map. The presented open source approach for digital surface model delivery has been compared with pure commercial approach. The commercial approach, for the same case and area, has been performed by a state of art commercial MAV technology and software. Results show differences between both approaches in data processing, accuracy and digital surface modeling. The paper concludes both process usability and ability to perform a geodetic grade surface modeling within presented case, and foreseen its usability of Open Drone Map toolkit for academic education purposes and researches.
-
Evaluation of organic coating systems for corrosion protection of industrial equipment using impedance spectroscopy
- Andrzej Miszczyk
- Kazimierz Darowicki
The high economic impact of corrosion can be reduced by enhanced corrosion management and prevention based on appropriate means. This applies in particular to the protection of structures with organic protective coatings. Steel is subject to corrosion that reduces its service life and leads to destruction in most severe cases. The application of paints to metallic objects for corrosion control has been known for a long time and is nowadays the most popular technology of metal protection. High-performance coatings must meet specific performance requirements as well as environmental regulations. Recently, constantly increasing requirements about the anti-corrosion coatings combined with cost and environmental awareness make the need for smart coating selection for corrosion protection of industrial equipment and structures. A new approach to select protective systems for heavy, specific industrial environments has been proposed. To achieve this aim it uses evaluation of barrier and adhesional aspects of coating protection after short natural exposure.
-
Evaluation of propagation parameters of open guiding structures with the use of complex root finding algorithms
- Małgorzata Warecka
- Piotr Kowalczyk
- Rafał Lech
An efficient complex root tracing algorithm is utilized for the investigation of electromagnetic wave propagation in open guiding structures. The dispersion characteristics of propagated and leaky waves are calculated for a couple of chosen waveguides. The efficiency of the root tracing algorithm is discuses and compared to a global root finding algorithm.
-
Evaluation of Readiness of IT Organizations to Agile Transformation Based on Case-Based Reasoning
- Miłosz Kurzawski
- Cezary Orłowski
- Tomasz Deręgowski
- Artur Ziółkowski
Nowadays many of IT organization decides to change the way of delivering from classic, waterfall approach to agile. This transition is called “agile transformation” (AT). The problem of this process is that part of companies started AT without any analysis. This causes that many of transitions fails and organizations must return to old methods of delivering. Cost of return is significant and number of projects with violated project management triangle is bigger than before. In this paper authors described the results of conducted research and the model of evaluating of readiness to agile transformation based on case-based reasoning.
-
Evaluation of Respiration Rate Using Thermal Imaging in Mobile Conditions
- Jacek Rumiński
- Alicja Kwaśniewska
Respiratory rate is very important vital sign that should be measured and documented in many medical situations. The remote measurement of respiration rate can be especially valuable for medical screening purposes (e.g. severe acute respiratory syndrome (SARS), pandemic influenza, etc.). In this chapter we present a review of many different studies focused on the measurements and estimation of respiration rate using thermal imaging methods. Additionally, we present results of our research focused on the evaluation of different respiration rate estimators for the needs of data processing of image sequences recorded by small, mobile thermal cameras. We used small thermal camera modules in the prototypes of smart glasses for the evaluation of different parameters related to respiration activities. The chapter presents the used methodology and results of the respiration rate analysis, detection of apnea events, description of respiration patterns and other parameters that can be analyzed for respiration waveforms derived from the regions of the nostrils or mouth in thermal video sequences.
-
Evaluation of Response Amplitude Operator of Ship Roll Motions Based on the Experiments in White Noise Waves
- Sebastian Bielicki
- Marek Kraskowski
- Antoni Bednarek
Evaluation of the response amplitude operator (RAO) function for ship wave frequency motions by means of scale model tests in regular waves is a standard procedure conducted by hydrodynamic model testing institutions. The resulting RAO function allows for evaluating sufficiently reliable seakeeping predictions for low to moderate sea states. However, for standard hull forms, correct prediction of roll motion in irregular wave (and also in regular waves different than these used in the experiment) on the basis of RAO function presents a substantial challenge due to considerable contribution of viscous damping to roll response. In other words, the RAO values depend strongly on the amplitude of the waves used in the experiment, so the final prediction requires careful application of relevant correction of RAO, dependent on the actual significant wave height, for which the prediction is computed. Thus, in order to collect complete data for ship roll prediction, the roll decay test is usually also required. Additional drawback of evaluating the seakeeping prediction on the basis of RAO is the fact that the experiment in regular waves is quite time-consuming, which refers to the experiment itself as well as to the processing. The following paper presents a proposal of the alternative method for experimental evaluation of response amplitude operator of roll motion in beam waves, consisting in exposing the ship model to irregular wave characterized by white noise spectrum, i.e. the spectrum of uniform energy density. In theory, RAO function is equivalent to the square root of the spectrum of the response to white noise wave. The results of experiments in white noise waves were verified on the basis of the results of comprehensive experiments conducted in usual way. Additionally, the effect of non-linearity of viscous damping was widely studied by comparing the calibrated RAO-based predictions with actual response to irregular waves of different heights. As a result, a method for including the non-linear effects in prediction based on white noise was proposed. It was proved that the proposed method is capable of providing equally valuable information in significantly shorter time.
-
Evaluation of structural change during fast transformation process of cross-linked NR into liquid NR by light pyrolysis
- Xiaoyu Wu
- Krzysztof Formela
- Raqiqa Rasool
- Shifeng Wang
The presence of cross-linked networks in rubber creates a tremendous problem for recycling and reusing of waste rubber. Fast transformation of cross-linked natural rubber (NR) into liquid natural rubber was carried out by light pyrolysis in temperature range from 240 to 300 °C in variable time (in range: 1–30 min). The transformation efficiency was evaluated by measuring the sol fraction and the cross-link density of the gel fraction. Over 80 wt% sol fraction was obtained at 280 °C in 15 min and 100 wt% sol fraction was obtained at 300 °C in 3 min. The chemical structure of sol fraction was characterized by gel permeation chromatography, nuclear magnetic resonance and infrared spectroscopy. The molecular weight of sol fraction in cross-linked NR processed at 280 °C and 300 °C decreased when gel fraction is over 50%. The nuclear magnetic resonance results showed that mono-sulfidic linkages occurred mainly in the sol fraction of liquid NR obtained at 300 °C. Isomerization from cis to trans form of isoprene unit in NR increased with extending pyrolysis time.
-
Evaluation of the factors influencing business bankruptcy risk in Poland
- Tomasz Korol
This article is devoted to the issue of assessing the causes of business failure. The presented studies answer two research questions – what are the causes of corporate bankruptcies in Poland and how to more efectively predict the scale of bankruptcies in the country. The author has conducted a study to analyze the specic endogenous and exogenous causes of company bankruptcy depending on the type of the bankruptcy with consideration of the three different phases of the crisis in enterprises. The research is based on 185 companies (60 bankrupt and 125 non-bankrupt rms) listed on the Warsaw Stock Exchange. For each company the author has calculated 14 different financial ratios for each of the six years before classifying the firm as bankrupt or non-bankrupt. The author has also done research to identify specific macroeconomic variables affecting the bankruptcy process of the companies in Poland. This provided specification of the manner and how strongly the various factors affect the quantity and intensity of bankruptcy applications in this region of Europe. Additionally, with the use of selected macroeconomic variables the author programmed a fuzzy logic model to forecast the general intensity of bankruptcies in Poland. This study is the first attempt at using fuzzy logic to predict the risk of bankruptcy in a macro aspect. The results demonstrate the great potential of this method. The received effectiveness of the fuzzy logic model is at the level of 84%.
-
EVENTS VISUALIZATION POST IN A DISTRIBUTED TELEINFORMATION SYSTEM FOR THE BORDER GUARD
- Bartosz Czaplewski
- Sylwester Kaczmarek
- Jacek Andrzej Litka
Events Visualization Post is a part of the STRADAR project, which is dedicated to streaming real-time data in distributed dispatcher and teleinformation systems of the Border Guard. Events Visualization Post is a software designed for simultaneous visualization of data of different types. In the paper, the structure of the software is presented, the process of generation of tasks is described, and the visualization of audio, files, and images is shown.
-
Evolutionary music composition system with statistically modeled criteria
- Zdzisław Kowalczuk
- Marek Sylwester Tatara
- Adam Bąk
The paper concerns an original evolutionary music composition system. On the basis of available solutions, we have selected a finite set of music features which appear to have a key impact on the quality of composed musical phrases. Evaluation criteria have been divided into rule-based and statistical sub-sets. Elements of the cost function are modeled using a Gaussian distribution defined by the expected value and variance obtained from an analysis of recognized music pieces. An evolutionary algorithm, considering a reference sequence of chords as an input, is created, implemented and tested. The results of a sampling survey (poll) proves that the melodies generated by the system arouse the interest of a listener.
-
Ewaluacja interwencji w obszarze transportu miejskiego i aglomeracyjnego - stan obecny vs pożądany oraz próba standaryzacji metodyki badań
- Krzysztof Grzelec
- Olgierd Wyszomirski
Interwencjonizm publiczny polega na realizacji polityki ekonomicznej i społecznej poprzez aktywne oddziaływania państwa za pomocą instrumentów na sferę produkcji, podziału, wymiany i konsumpcji. Interwencjonizm wynika z faktu niedoskonałej regulacji działalności na rynkach usług transportowych. W transporcie, podobnie jak w innych dziedzinach gospodarowania, nie jest możliwe osiągnięcie efektywności ekonomicznej, jeżeli ceny za świadczone usługi nie odzwierciedlają faktycznie ponoszonych kosztów wewnętrznych i zewnętrznych ich wytworzenia. Interwencjonizm publiczny w transporcie jest zdeterminowany realizacją celów polityki transportowej, a w transporcie pasażerskim także dążeniem do jego integracji.
-
EXAMINATION OF SOL-GEL DERIVED HYDROXYAPATITE ENHANCED WITH SILVER NANOPARTICLES USING OCT AND RAMAN SPECTROSCOPY
- Maciej Głowacki
- Marcin Gnyba
- Paulina Strąkowska
- Mateusz Gardas
- Maciej Kraszewski
- Michał Trojanowski
- Marcin Strąkowski
Hydroxyapatite (HAp) has been attracting widespread interest in medical applications. In a form of coating, it enables to create a durable bond between an implant and surrounding bone tissues. With addition of silver nanoparticles HAp should also provide antibacterial activity. The aim of this research was to evaluate the composition of hydroxyapatite with silver nanoparticles in a non-destructive and non-contact way. For control measurements of HAp molecular composition and solvent evaporation efficiency the Raman spectroscopy has been chosen. In order to evaluate dispersion and concentration of the silver nanoparticles inside the hydroxyapatite matrix, the optical coherence tomography (OCT) has been used. Five samples were developed and examined ‒ a reference sample of pure HAp sol and four samples of HAp colloids with different silver nanoparticle solution volume ratios. The Raman spectra for each solution have been obtained and analyzed. Furthermore, a transversesectional visualization of every sample has been created and examined by means of OCT.
-
Examination of the epoxy coating system's resistance to Corrobill
- Kazimierz Darowicki
- Stefan Krakowiak
- Tadeusz Sonneck
The tests of the influence of the surface cleaning agent on the epoxy coating were carried out. Electrochemical and corrosion tests were carried out. The effect of the preparation on the adhesion and hardness of the tested coating was tested.