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Number of results: 88
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Abstract

In the paper, the author presents the application of thermography method for investigation of elastic-plastic states in two-dimensional models. The experimental testing was carried out on the duralumin elements with different stress concentrators loaded by uniformly distributed tensile stresses. The changes of temperature distribution on the surface of the models during loading process were recorded by a thermovision camera. On the basis of calibrating test carried out on the stretched element, the relationship between loading, temperature increment and specimen elongation was determined. Quantitative temperature distribution in chosen cross-sections of the models was determined using thermograms received for various levels of loading. On the basis of the obtained results, the author estimated the accuracy of the method as well as its usability for investigation of the plastic zones' localization and propagation.
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Abstract

In the paper, the author presents experimental analysis of propagation of plastic zones in two-dimensional models with different stress concentrators. The experimental tests were carried out by photoelastic coating method on duralumin stripes loaded by tensile stresses. For various levels of loading, the photographs of isochromatic pattern were taken under loading and after removing loading. On the basis of isochromatic pattern recorded for loaded models, the boundaries of plastic zones were determined using the Treska-Coulomb yield condition. The isochromatic pattern taken for the unloaded, but previously partly plastified elements, show the picture of the residual strain remaining in the material. A discussion of the results is presented.
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Abstract

The subject discussed in this paper is the evolution of the ideas of organic development in urban planning, focused on the waterfront areas. The paper also aims to analyze and interpret current trends in urban water waterfront planning, which are infl uenced by the contemporary ideas related to environmental issues, landscape planning, new technologies in the fi eld of building design and civil- and hydroengineering or application of the renewable energy sources.
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Abstract

This study examined the effects of UV-B radiation and allelochemical stress induced by ferulic acid (FA) on the activity of phenylalanine ammonia lyase (PAL; EC 4.3.1.5) at metabolic and molecular levels in two cucumber genotypes differing in tolerance to cold and disease, in order to determine any interaction between stress effects and genotype response. Stresses were applied simultaneously, sequentially, and singly. In both genotypes, several days of UV radiation retarded growth up to 36%. The effect of FA was not significant. The response to a particular stress, including the effect on PAL activation, was enhanced by simultaneous application of the two stresses. PAL transcription was not correlated with the increase of PAL activity. Exposure to UV-B, FA, and combined UV-B and FA was detrimental to both genotypes but to different extents. The response was not correlated with the genotype of cold and disease sensitivity. PAL activity and its transcription seem to be involved in UV and allelochemical stress, but not related to the plants' tolerance of these stresses.
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Abstract

For over twenty years psychologists have been using information and communication technology to design solutions aimed at improving mental health and quality of life of their clients or patients. One of those solutions are internet interventions. Although these interventions are commonly used in other countries, knowledge about them in Poland is limited. The aim of the article is to introduce to the topic of psychological internet interventions by describing the basic functionalities of internet interventions, the context of their use, their classification, areas where they can be applied and challenges related to their future development and wider implementation.
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Abstract

This paper presents for the first time X-ray computed microtomography (μCT) analysis as a technique for Silurian graptolite detection in rocks. The samples come from the Jantar Bituminous Claystones Member of the Opalino core, Baltic Basin, northern Poland. Images were obtained with spatial resolution of 25 μm, which enabled the authors to create a 3-D visualization and to calculate the ratio of fissure and graptolite volume to the total sample volume. A set of μCT slices was used to create a 3-D reconstruction of graptolite geometry. These μCT slices were processed to obtain a clearly visible image and the volume ratio. A copper X-ray source filter was used during exposure to reduce radiograph artifacts. Visualization of graptolite tubaria (rhabdosomes) enabled Demirastrites simulans to be identified. Numerical models of graptolites reveal promising applications for paleontological research and thus for the recognition and characterization of reservoir rocks.
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Abstract

The paper approaches an important issue of the phonological similarity of words, relevant for current research in phonotactics, word recognition, production and acquisition, by analyzing the data collected in an experiment in which 30 native speakers of Polish were asked to provide phonologically similar words to 80 nonwords. The study demonstrates that the uncovered patterns of phonological similarity (segment substitutions, deletions and additions, the use of bigrams, trigrams and quadrigrams, noncontiguous sounds and segment metathesis) go beyond the commonly employed concept of neighbourhood density and point to the need to revise the current approaches to phonological similarity of words. It is argued that the experimental results can be attributed to the considerably more complex phonotactic and morphological structure of Polish than English.
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Abstract

Jeśli spojrzymy na strukturę urbanistyczną Warszawy poprzez ocenę wartości historycznych założeń przestrzennych, tych które wiążą miasto z najcenniejszymi osiągnięciami urbanistyki europejskiej, to niewątpliwie w środowiskach profesjonalnych barokowe założenie Osi Saskiej znajdzie się wśród najczęściej dostrzeganych i wymienianych. Jak wiadomo, w swojej koncepcji nawiązuje ono bezpośrednio do Wersalu, gdzie rezydencja królewska, kompozycja ogrodowa i nowo rozplanowane elementy struktury miasta tworzą współosiową, wielkoprzestrzenną kompozycję o nieskończonych, dalekich zasięgach. Badania historyczne potwierdzające związek obu tych założeń, właśnie na ich wspólne odniesienia ideowe i formalne zwracają szczególną uwagę. Podkreślają „nieskończony”, zachodni zasięg kompozycyjny Osi Saskiej przedłużony w układzie ról dalekiej Woli, oraz równie dalekie otwarcie w kierunku wschodnim, którego kontynuację przekraczającą wnętrze Krakowskiego Przedmieścia i skarpę dostrzega się w przedłużeniu koryta starorzecza Wisły i związkach z otwartym krajobrazem brzegu Pragi, wówczas jeszcze słabo na tym odcinku zurbanizowanym.
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