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Number of results: 8
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Abstract

The purpose of this study is to investigate a structure’s response to blast loading when composite columns are used instead of conventional reinforced concrete (RC) cross sections and when a conventional structure is retrofitted with braces. The study includes conducting dynamic analyses on three different structures: a conventional reference RC structure, a modified structure utilizing composite columns, and a modified structure retrofitted with steel braces. The two modified structures were designed in order to investigate their performance when subjected to blast loading compared to the conventional design. During the dynamic analyses, the structures were exposed to simulated blast loads of multiple intensities using the finite-element modelling software, SeismoStruct. To evaluate their performance, the responses of the modified structures were analyzed and compared with the response of the conventional structure. It was concluded that both the structure with composite columns and the steel brace structure experienced less damage than the conventional model. The best performance was obtained through the steel brace structure.

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Authors and Affiliations

Y.E. Ibrahim
M. Almustafa
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Abstract

The article presents probable consequences for the protection of deposits and other mining needs, related to the entry into force of the Act of July 5, 2018 on the Facilitation of the Preparation and Implementation of Housing Investments and Accompanying Investments. This act introduces facilities for the preparation and implementation of housing as well as related projects, including the possibility of introducing investments incompatible with the existing local plans. In addition, it does so in a situation where land reserves for housing development, both in local plans and in studies of conditions and directions of spatial development, many times exceed the future needs of our country.

The article presents the fundamental changes introduced by the Act to the existing planning and spatial planning system, as well as the risks associated with the mining industry. Among the latter, the following can be mentioned: lower stability of local law regulations, the possibility of resolving changes in spatial development at a very fast pace, without providing an effective way to inform subjects that may be threatened by these changes and increase the probability of the appearance of investments in the area of mining, the neighborhood of which may lead to limit or even liquidate these installations, due to even their disadvantages to housing. Some remedies have been proposed to mitigate some of the threats in the article.

The Act in question was prepared and passed at an express pace, with a large opposition from many environments. At the same time, a number of legal solutions were applied in it, which were not applied in the Polish law. As a result, there are many doubts about the effects of its introduction.

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Authors and Affiliations

Marek Wiland
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Abstract

The article discusses the phenomenon of the existence of different languages in the public space in Scuol, a famous tourist locality and health resort in the Swiss canton of Grisons. The offi cial language of the town is Romansh, but all citizens speak fl uently also German that has become the second “mother”-tongue of the local population. The author analyses the complexity of the linguistic landscape in the town concentrating of the visible texts in the shops of the commercial center. From the research work results that German is the most visible language. Romansh appears in the fi rst place in the names of the shops and in the information about the opening times. Other texts in Romansh are scarce and they emerge in the most cases with the parallel texts in German. English plays as the global language an important role too, mostly in the advertising of expensive and prestigious products but also in more common contexts. Other languages appear only exceptionally. The relatively unimportant role of Romansh and the dominating position of German reveal that the existence of the oldest language of Switzerland in Scuol is endangered.
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Authors and Affiliations

Lesław Tobiasz
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Abstract

In Western music culture instruments have been developed according to unique instrument acoustical features based on types of excitation, resonance, and radiation. These include the woodwind, brass, bowed and plucked string, and percussion families of instruments. On the other hand, instrument performance depends on musical training, and music listening depends on perception of instrument output. Since musical signals are easier to understand in the frequency domain than the time domain, much effort has been made to perform spectral analysis and extract salient parameters, such as spectral centroids, in order to create simplified synthesis models for musical instrument sound synthesis. Moreover, perceptual tests have been made to determine the relative importance of various parameters, such as spectral centroid variation, spectral incoherence, and spectral irregularity. It turns out that the importance of particular parameters depends on both their strengths within musical sounds as well as the robustness of their effect on perception. Methods that the author and his colleagues have used to explore timbre perception are: 1) discrimination of parameter reduction or elimination; 2) dissimilarity judgments together with multidimensional scaling; 3) informal listening to sound morphing examples. This paper discusses ramifications of this work for sound synthesis and timbre transposition.

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Authors and Affiliations

James Beauchamp
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Abstract

Protection of the environment and counteracting global warming require finding alternative sources of energy. One of the methods of generating energy from environmentally friendly sources is increasing the share of gaseous fuels in the total energy balance. The use of these fuels in compression-ignition (CI) engines is difficult due to their relatively high autoignition temperature. One solution for using these fuels in CI engines is operating in a dualfuel mode, where the air and gas mixture is ignited with a liquid fuel dose. In this method, a series of relatively complex chemical processes occur in the engine's combustion chamber, related to the combustion of individual fuel fractions that interact with one another. Analysis of combustion of specific fuels in this type of fuel injection to the engine is difficult due to the fact that combustion of both fuel fractions takes place simultaneously. Simulation experiments can be used to analyse the impact of diesel fuel combustion on gaseous fuel combustion. In this paper, we discuss the results of simulation tests of combustion, based on the proprietary multiphase model of a dual-fuel engine. The results obtained from the simulation allow for analysis of the combustion process of individual fuels separately, which expands the knowledge obtained from experimental tests on the engine.

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Authors and Affiliations

Maciej Mikulski
Sławomir Wierzbicki
Andrzej Piętak
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Abstract

In the paper a new implementation of a compact smart resistive sensor based on a microcontroller with internal ADCs is proposed and analysed. The solution is based only on a (already existing in the system) microcontroller and a simple sensor interface circuit working as a voltage divider consisting of a reference resistor and a resistive sensor connected in parallel with an interference suppression capacitor. The measurement method is based on stimulation of the sensor interface circuit by a single square voltage pulse and on sampling the resulting voltage on the resistive sensor. The proposed solution is illustrated by a complete application of the compact smart resistive sensor used for temperature measurements, based on an 8-bit ATxmega32A4 microcontroller with a 12-bit ADC and a Pt100 resistive sensor. The results of experimental research confirm that the compact smart resistive sensor has 1°C resolution of temperature measurement for the whole range of changes of measured temperatures.

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Authors and Affiliations

Zbigniew Czaja
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Abstract

The end−Permian mass extinction constituted a major event in the history of crinoids. It led to the demise of the major Paleozoic crinoid groups including cladids, disparids, flexibles and camerates. It is widely accepted that a single lineage, derived from a late Paleozoic cladid ancestor (Ampelocrinidae), survived this mass extinction. Holocrinid crinoids ( Holocrinus , Holocrinida) along with recently described genus Baudicrinus (Encrinida), the only crinoid groups known from the Early Tria ssic, are considered the stem groups for the post−Paleozoic monophyletic subc lass Articulata. Here, we report preliminary data on unexpectedly diverse crinoid faunas comprisin g at least four orders from the Lower Triassic (Induan and Olenekian) of Svalbard, extending their stratigraphic ranges deeper into the early Mesozoic. These findings strongly imply that the recovery of crinoids in the aftermath of the end−Permian extinction began much earlier at higher palaeolatitudes than in the central Tethys.
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Authors and Affiliations

Mariusz A. Salamon
Nils−Martin Hanken
Przemysław Gorzelak
Henrik Erevik Riise
Bruno Ferré
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Abstract

The eight most abundant species (mean density >20 ind. m −2 ), which occurred at high frequencies (mean >30%) were selected from grab samples in the three Svalbard fjords: Hornsund, van Mijenfjord, and Kongsfjord, in the summer seasons between 1997 and 2007. Six polychaete and two bivalve species comprised more than 47% of the individuals and the biomass in all the samples examined. Four species are cosmopolitan, while the others are widely distributed Arctic−boreal species, and none has Arctic origin. Their density, frequency of occurrence, and biology are very similar across the wide geographical range from boreal to Arctic conditions. As the diversity of benthic fauna in the fjords studied increases (from 172 to 238 species), the dominance of the eight species in the soft bottom community diminishes from 76% to 47%. In times of hydrological regime shift, i.e. , the warming of the European Arctic, it is unlikely that the abundancy of these species in the soft bottom fjordic ecosystems will change. The most common soft bottom species are not good indicators of environmental change in the Arctic, and rare, specialized species are better option for indicative purposes.
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Authors and Affiliations

Jan Marcin Węsławski
Maria Włodarska-Kowalczuk
Monika Kędra
Joanna Legeżyńska
Lech Kotwicki

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