2013 - Repozytorium publikacji - Politechnika Gdańska

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Publikacje z roku 2013

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The point estimate method in a reticulated shell reliability analysis
- Jarosław Przewłócki
- Jarosław Górski
- Przemysław Sorn
2013
The objective of this paper is to present an application of the point estimate method (PEM) that can determine the probabilistic moments for engineering structures. The method is reasonably robust and adequately accurate for a wide range of practical problems. It is a special case of numerical quadrature based on orthogonal polynomials. The main advantage of this method is that, unlike FORM or SORM, it is not necessary to carry on laborious differentiations and in the case of the Monte Carlo simulation, calculations are repeated only several times. The method is straightforward, easy to use, and requires little knowledge of probability theory. This approach is illustrated by two examples: an estimation of the critical force in linear elastic buckling analysis and a reticulated shell limit load calculations. In the case of the Euler’s problem of the elastic beam two uncertain quantities were considered: buckling length and Young’s modulus. It is assumed that both variables are random, normally distributed, and independent. For the reticulated shell the geometric imperfections are considered.
The Point Estimate Method in a Reticulated Shell Reliability Analysis
- Jarosław Przewłócki
- Jarosław Górski
- Przemysław Sorn
2013
The objective of this paper is to present an application of the point estimate method (PEM) to determine the probabilistic moments for engineering structures. Reliability analysis is illustrated by two examples: an estimation of the critical force in linear elastic buckling analysis and a reticulated shell limit load determinations. Calculations were also made using Monte Carlo method. It has been shown the practical usefulness of the PEM and highlights the advantages of this method.
THE POTENTIAL OF DIFFERENT VARIETIES OF WHITE CABBAGE IN PHYTOREMEDIATION OF ZN AND CD
- Marzena Szczygłowska
- Piotr Konieczka
2013
The species belong to the botanical family Brassi- caceae are considered to be useful for phytoremediation of soil contaminated with heavy metals. Problems with use the plants recognized as hyperacumulators is that, the plants need to be harvested shortly after the plants become mature, which causes problems of disposal of obtained biomass. When these plants are dried, they easily crumble and flake off, greatly reducing the yield obtained, and the rest of the plant residues are a source of sec- ondary emission of toxic substances. Quite a large biomass and the lack of difficulties after harvesting are advantages described for different types of cabbage. Our study reveals the usefulness of the white cabbage ( Brassica oleracea L. subsp. capitata f. alba ) for the purification of the soil from zinc and cadmium by phytoextraction
The potential of historical railway infrastructure, possibilities of its adaptation on the examples of railway water towers
- Magdalena Podwojewska
2013
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The reasons of considarable deflections of roof trusses in engineering analysis
- Joanna Wojtas
- Jacek W. Kaczmarek
- Jarosław Przewłócki
2013
The aim of the paper is to present an unconventional analysis of deformations of roof trusses of an exhibition pavilion. Structure of the main hall of the pavilion consists of repeatable span frames with steel pillars made of I-sections, fastened in the foundations and hinged supporting roof girders. The roof trusses, completed in steel construction, have undergone considerable permanent deflections. Deformations of the lower chord joints were much higher in comparison with calculated deflections due to the actual loads of the roof. A series of static strength analyses was conducted, including an actual work of the troughed sheet, for different variants of the truss modes. Their impact on capacity of particular elements of the girder was studied. The aim of such analyses was to determine the value of the snow loads and its distribution. Detailed examination of the problem and the causes of deformations of the roof allowed for the decision to keep the deformed roof trusses which in spite of partial softening and permanent deformations, still operate efficiently in the elastic state for loads which the roof was designed for. Once loading test was completed, the object was put to use and it has been operating properly till the present day.
The research of glass-ceramics implants used for bone pitches to examine bacteria adhesion occuring in human body
- Beata Świeczko-Żurek
2013 Pełny tekst Engineering of Biomaterials / Inżynieria Biomateriałów
The paper deals with the research concerning the bacteria adhesion on bioactive glass - ceramics materials
The role of epigenetics in regeneration
- Justyna Podolak-Popinigis
- Bartosz Górnikiewicz
2013
Complex changes in chromatin structure and at the transcriptional level occur from the creation of a single parental gamete throughout fertilization, embryo development and the life of an adult organism. Epigenetic changes, such as methylation and hydroxymethylation of DNA or histone methylation and acetylation, are an important part of these processes. Epigenetic regulation has an essential inﬂuence on gene expression level. DNA methylation in promoter regions of genes results in the inhibition of their transcription. It is known that the ability of pluripotent stem cells to diﬀerentiate corresponds to genomic DNA methylation patterns, while a few studies have also reported that the capability to re-grow damaged tissues in regenerative processes is associated with epigenetic changes. In addition to embryonic stem cells diﬀerentiation, epigenetic regulation of regeneration has been found to be pivotal for limb regeneration in the tadpole of Xenopus laevis and muscle repair after damage in mammals.
The role of rewards and demands in burnout among surgical nurses
- Beata Basińska
- Ewa Wilczek-Rużyczka
2013 Pełny tekst International Journal of Occupational Medicine and Environmental Health
Objective: Job rewards have both, an intrinsic and an extrinsic motivational potential, and lead to employees’ development as well as help them to achieve work goals. Rewards can balance job demands and protect from burnout. Due to changes on the labour market, new studies are needed. The aim of our study was to examine the role of demands and individual rewards (and their absence) in burnout among surgical nurses. Materials and Methods: The study was conducted in 2009 and 2010 with 263 nurses who worked in surgical wards and clinics in hospitals in Southern Poland. The hypotheses were tested by the use of measures of demands and rewards (Effort-Reward Imbalance Questionnaire by Siegrist) and burnout syndrome (Maslach Burnout Inventory). A cross-sectional, correlational study design was applied. Results: Nurses experienced the largest deficiencies in salary and prestige. Exhaustion was explained by stronger demands and lack of respect (large effect). Depersonalization was explained by stronger demands, lack of respect and greater job security (medium effect). Reduced personal achievement was explained by more demands and greater job security (small effect). Conclusions: Excessive de- mands and lack of esteem are key reasons for burnout among surgical nurses. Job security can increase burnout when too many resources are invested and career opportunities do not appear. These results may help to improve human resource management in the healthcare sector.
The Role of Thermal Monitoring in Cardiosurgery Interventions
- Antoni Zbigniew Nowakowski
- Mariusz Kaczmarek
- Jan Rogowski
2013
The results of a research project devoted to the analysis of the value of IR-thermal imaging in monitoring the quality of cardiosurgery interventions are presented. The role of the ADT is underlined.
The role of trade in intra industry productivity growth - the case of old and new European Union countries.
- Aleksandra Parteka
2013 Review of Development Economics
The purpose of this paper is to evaluate the role of trade in productivity growth in a sample of 30 sectors in 25 EU countries in the period of rapid East–West integration (1995–2007). Shift-share analysis is used to show that changes in value added per hour worked in these countries appear to be mainly due to positive developments (rising productivity) within single industries and only to a lower extent result from a shift towards higher productivity activities. Trade is found to be an important positive determinant of intra-industry productivity growth in European countries. Exports and imports alike can be associated with efficiency gains, but intermediate good exchange and trade with New Member States exert a particularly strong influence on intra-industry productivity growth in the EU
The semi-Markov model of the process of appearance of sea-going ship propupsion system ability and inability states in application to determining the reliablity of these systems
- Jerzy Girtler
2013 Pełny tekst Polish Maritime Research
The article presents possible application of the theory of semi-Markov processes in creating the eight-state model of the process of appearance of the propulsion systems ability and inability states on sea-going vessels performing transportation tasks in a relatively long operating time t (t → ∞). The model has been proved to be able to be successfully used for determining the reliability of the abovementioned systems. The probability of faultless operation in time t was assumed the measure of system reliability. Operating situations of sea-going vessels were characterised, with special attention being paid to the fact that the loads of propulsion system components of these vessels are of random nature. These loads lead to damages which for this reason were also considered random events. It was also assumed that the damages provoke the appearance of states of inability of particular ship propulsion system components which means that these states are random events as well. The states of ability of a given ship propulsion system have been assumed to exist when all components of this system are in the state of ability. In case when at least one component is in the state of inability, the entire system is in the state of inability. Conditions were formulated for the reliability model of an arbitrary system to be able to be worked out in the form of the semi-Markov process. The need for the use of technical diagnostics in reliability examination of sea-going ship propulsion systems was indicated. In conclusions, certain qualities of the article were highlighted which are, in author’s opinion, of highest importance in reliability examination of sea-going ship propulsion systems.
The shallow sea experiment with usage of linear hydrophone array
- Grażyna Grelowska
- Eugeniusz Kozaczka
- Ignacy Gloza
- Sławomir Kozaczka
2013
Purpose of this article is to present designed and made linear hydrophone array and the results obtained during in situ trails on Gulf of Gdańsk. The measuring system allowed to localize hydrophones in the selected points and perform measurements in both the horizontal antenna positioning and vertical. Made in this way recordings allow creating accurate 3D imaging of sound intensity/propagation. During research three floating objects were measured: small ship (18 meters long), yacht (12 meters long) and 5 meters pontoon with engine and paddles used to drive. In the article accurately will be described the entire measurement system and complementary devices (navigation system, sound speed profiler, online underwater monitoring to control linear antenna position) and procedures used during in situ measurement circuit check and calibration using Lubell Underwater Speaker with amplifier and connected generator with set of reference signals. Characteristic arrangement of sensors allows use of hyperbolic navigation algorithms which results will be presented with an emphasis on measurements when the unit performed circulation around the measurement system. Furthermore some spectrograms, cross correlations and frequency classification dependence of the speed using a prepared script in Matlab programming environment will be discussed and presented.
The situation of young mothers in the Polish labour market
- Anita Richert-Kaźmierska
2013
The purpose of the article is to present the situation of young women combining professional and paternal responsibilities in the Polish labour market. The papaer presents the results of interviews conducted with six young mothers.
The speciation of organotin compounds in sediment and water samples from the port of Gdynia
- Barbara Radke
- Andrzej Wasik
- Linda Jewell
- Jacek Namieśnik
2013 SOIL & SEDIMENT CONTAMINATION
Organotin compounds (OTC) are toxic towards all living organisms. The application of organitin-based antifouling systems is becoming the main source of OTC in the ocean. Harbor sediments and water contain large deposits of organotin compounds due to application of antifouling systems in the shipping industry. OTC contamination presents a potential risk to the marine environment. Sediment and water samples were collected in 2009 from Gdynia Harbor. For all the analyzed organotin compounds, the mean concentration values were determined: water samples monobutyltin (MBT): 13.2, dibutyltin (DBT): 16.7, tributyltin (TBT): 60.7 (ng cation dm−3), and sediment samples MBT: 261.4, DBT: 751.9, TBT: 2148.2 (ng cation g−1 d.w.). The estimated content of monophenyltin (MPhT), diphenyltin (DPhT), triphenyltin (TPhT), monooctyltin (MOT), dioctyltin (DOT), and tricyclohexyltin (TCHT) were below the detection limit of the applied method. It was found that the content of organic matter, the amount of fine fraction, and the pH all play a significant role in the distribution and sorption process of OTC between the water and the sediment on the bottom. Compared to an earlier study, the concentrations of all OTC are much lower, confirming that the applied legislation has had a positive impact.
The study of structure and surface morphology of lithium titanate sol-gel derived thin films
- Marcin Stanisław Łapiński
- Barbara Kościelska
- Wojciech Sadowski
2013 JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
In this paper the structure and the surface morphology of lithium titanate (LTO) thin films are presented. Nanocrystalline thin films were prepared by sol–gel method. To examine the influence of the annealing time on as-prepared films crystallization, the coatings were heated at different temperatures in the range of 500 °C–600 °C for 10, 20, 40 and 80 h. The structure of the obtained material was investigated using the X-ray diffraction (XRD) method, while the surface was studied with scanning electron microscope (SEM). Additionally contact angle measurements were performed according to the sessile drop method. A significant influence of annealing time on formation of crystalline phase was shown by XRD measurements. Correlation between heating time and grain sizes was noticed. On SEM images high homogeneity of prepared films was observed.
The Successful Case of Social Cooperative 50+ as an Example of Value Creation
- Marzena Starnawska
- Magdalena Olczyk
2013
The article presents the successful case of social cooperative 50+ as an Example of Value Creation. Authors discuss an idea of social enterprises and social cooperatives and success factors of them.
The Towers of Hanoi as a Cyber-Physical System Education Case Study
- Pieter J. Mosterman
- Justyna Zander
- Zhi Han
2013
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The unrecognized and untapped potential of workers aged >=50 years: myth or fact, a study of the situation of the elderly workers in Poland
- Anita Richert-Kaźmierska
- Katarzyna Stankiewicz
2013 Scandinavian Journal of Work, Environment & Health
The authors carried out a comparative analysis and quantitative synthesis of the results of primary research from Polish research centers on Polish employers' assessment of workers aged 50 years old and more and the possibilities and conditionsof using the potential of this group in enterprises.
The use of innovative application in creating new marketing space for cultural and entertainment events in the local market
- Małgorzata Gwizdoń
- Maciej Głuszek
- Przemysław Kitowski
2013
The following article describes the problems concerning marketing of mass events in the local market and potential solutions. In the first part the barriers that occur in communication between the organizers and the articipants are defined. In the process of identifying problems the results of research conducted for the needs article were used. In following sections the solution with use of Smartphone app is shown. The features that should characterize the discussed tool are listed. In the final part of the presentation was discussed the possible ways of transferring the application.
The Use of Wavelet Analysis to Denoising of Electrocardiography Signal
- Dawid Gradolewski
- Grzegorz Redlarski
2013
The electrocardiography examination, due to its accessibility and simplicity, has an important role in diagnostics of the heart ailments. It enables quick detection of various heart defects, undetectable by other kinds of diagnostic tools, so it is very popular. Nevertheless, the measured signal is exposed to a different disturbances. Among them, the electromagnetic interferences, drift of reference electrode and high frequency noises occurring during the measure, should be included. The frequencies spectrum of the noise overlap the spectrum of the electrocardiography signal, which makes impossible to use a classical filters. In the human’s diagnosis, a high quality of the signal is of a great importance. Therefore, in this paper, an optimal wavelet denoising algorithm for electrocardiography signal is presented. The simulation shows that the use of wavelet analysis during the filtration process allows to remove effectively the noise from the electrocardiography signal, without losing an important information and also improves the quality of the signal. To obtain an unambiguous evaluation of wavelet denoising algorithms the signal-to-noiseratio (SNR), mean square error (MSE), and correlation coefficient were used simultaneously. What is more, a fit coefficient, determining the relation between original and denoised signal, were developed.