72 research outputs found
Geotechnical Aspects of Dike Construction Using Soil-Ash Composites
AbstractAn analysis of using of anthropogenic materials, mainly ashes from Coal Combustion Products (CCP), for dike construction is shown. Perspectives of anthropogenic materials application in geotechnical engineering and their advantages in sense of the carbon dioxide reduction are discussed. According to regulations of Kioto Protocol 2005 and EU agreement “Energy Roadmap 2050” recycled materials have higher usage priority than natural ones. General remarks about constructions using soil-ash composites are given with discussion about their properties and laboratory investigation. Finally the full-scale experiment within the DREDGDIKES Project (www.dredgdikes.eu) is described, which is focused on the new technology with the usage of dredged and anthropogenic materials for construction of dikes
On the origin of X-ray spectra in luminous blazars
Gamma-ray luminosities of some quasar-associated blazars imply jet powers
reaching values comparable to the accretion power even if assuming very strong
Doppler boosting and very high efficiency of gamma-ray production. With much
lower radiative efficiencies of protons than of electrons, and the recent
reports of very strong coupling of electrons with shock-heated protons
indicated by Particle-in-Cell (PIC) simulations, the leptonic models seem to be
strongly favored over the hadronic ones. However, the electron-proton coupling
combined with the ERC (External-Radiation-Compton) models of gamma-ray
production in leptonic models predict extremely hard X-ray spectra, with energy
indices about 0. This is inconsistent with the observed 2-10 keV slopes of
blazars, which cluster around an index value of 0.6. This problem can be
resolved by assuming that electrons can be cooled down radiatively to
non-relativistic energies, or that blazar spectra are entirely dominated by the
SSC (Synchrotron-Self Compton) component up to at least 10 keV. Here, we show
that the required cooling can be sufficiently efficient only at distances r <
0.03pc. SSC spectra, on the other hand, can be produced roughly co-spatially
with the observed synchrotron and ERC components, which are most likely located
roughly at a parsec scale. We show that the dominant SSC component can also be
produced much further than the dominant synchrotron and ERC components, at
distances larger than 10 parsecs. Hence, depending on the spatial distribution
of the energy dissipation along the jet, one may expect to see
gamma-ray/optical events with either correlated or uncorrelated X-rays. In all
cases the number of electron-positron pairs per proton is predicted to be very
low. The direct verification of the proposed SSC scenario requires sensitive
observations in the hard X-ray band which is now possible with the NuSTAR
satellite.Comment: 19 pages, 1 figure, accepted for publication in Ap
Structural control on the initiation and development of the Biała Wisełka Landslide Complex (Silesian Beskid, Outer Carpathians, Southern Poland)
The numerous landslides which have developed in the mostly Cretaceous to Eocene turbiditic rocks of the Silesian Beskid are genetically and geometrically controlled by bedrock structural features, the Biała Wisełka Landslide Complex being no exception. Its location is in the headwater area of the Wisła River, on the slopes of Mt. Barania Góra (1220 m a.s.l.). The bedrock is represented by flysch strata of the Silesian Nappe (Outer Carpathian Fold-and-Thrust Belt), or, more specifically, the Upper Cretaceous turbiditic Upper Godula and Lower Istebna Beds of the Godula Thrust Sheet. The research work consisted in their mapping and structural analysis, facilitated by the use of a high-resolution digital elevation model based on LiDAR data. A comparative analysis enabled the determination of the relationships between landslides and the bedrock structure. The study results point to significant roles being played by the joint network, fault systems, the structural arrangement and the lithology of rock strata in the initiation and evolution of the studied landslide complex. An additional result of the methods applied methods was the identification and characterization of previously unknown fault zones in the study area
Methods of modeling the demand for resources in the logistics sector
PURPOSE: Within the framework of this article, the authors review and analyze selected
methods of modelling the demand for resources in the logistics industry and application of
these methods as a tool to improve efficiency of logistics entities.DESIGN/METHODOLOGY/APPROACH: The general part contains a definition of the logistics sector
and its basic characteristics, as well as issues related to determining demand for resources
in the broader context of organization management. The detailed part discusses selected
methods of modelling the demand for resources, presenting the context of their application
and development perspectives of theoretical models for estimating demand for resources.FINDINGS: According to the principle of rational management, enterprises strive for the best
possible use of their resources. One of the means to achieve this goal is the proper
determination of demand for these resources, resulting from the current scale of operations
and expected changes in this area. In the logistics sector, which is an increasingly important
element of trade, and in many countries one of the key areas of the economy, the right
selection of resources affects both achieved financial results and operational possibilities of
providing services.PRACTICAL IMPLICATIONS: Results of the review indicate that correct determination of the
demand for resources is one of the key factors determining development of a market
advantage by individual participants in the exchange of goods.ORIGINALITY/VALUE: From the point of view of implementation of long-term goals of logistics
companies, strategic analyzes are of key significance, however, short-term analyzes are also
important, especially in ensuring current operational efficiency. Regardless of the time
perspective, planning models that limit the risk of inappropriate adjustment of resources to
the scale of operations, turn out to be useful.peer-reviewe
ANALIZA MOŻLIWOŚCI DETEKCJI WYŁADOWAŃ NIEZUPEŁNYCH W APARATURZE ROZDZIELCZEJ ŚREDNICH NAPIĘĆ W IZOLACJI POWIETRZNEJ METODĄ PRZEJŚCIOWEGO NAPIĘCIA DOZIEMNEGO
Modern switchgear increasingly use polymeric materials as insulation. Despite its numerous advantages they have limited resistance to partial discharge corrosion in some cases. In this paper noninvasive methods Transient Erath Voltage (TEV) measurement is proposed to detect various forms of partial discharges in medium voltage switchgear. These method allows for non-invasive diagnostic without switch of the switchgear. Measurement results confirm the effectiveness of the proposed approach.W nowoczesnej aparaturze rozdzielczej wykorzystuje się w coraz większym stopniu materiały polimerowe jako układy izolacyjne. Mimo swoich licznych zalet, wykazują one niekiedy ograniczoną wytrzymałość na wyładowania niezupełne. W artykule przedstawiono analizę możliwości wykorzystania nieinwazyjnej metody przejściowego napięcia doziemnego TEV do detekcji różnych form wyładowań niezupełnych w aparaturze rozdzielczej średnich napięć. Dzięki wykorzystaniu tej metody, diagnostyka odbywa się bez konieczności odstawiania urządzenia od systemu elektroenergetycznego. Uzyskane wyniki potwierdzają skuteczność metody
3C454.3 reveals the structure and physics of its 'blazar zone'
Recent multi-wavelength observations of 3C454.3, in particular during its
giant outburst in 2005, put severe constraints on the location of the 'blazar
zone', its dissipative nature, and high energy radiation mechanisms. As the
optical, X-ray, and millimeter light-curves indicate, significant fraction of
the jet energy must be released in the vicinity of the millimeter-photosphere,
i.e. at distances where, due to the lateral expansion, the jet becomes
transparent at millimeter wavelengths. We conclude that this region is located
at ~10 parsecs, the distance coinciding with the location of the hot dust
region. This location is consistent with the high amplitude variations observed
on ~10 day time scale, provided the Lorentz factor of a jet is ~20. We argue
that dissipation is driven by reconfinement shock and demonstrate that X-rays
and gamma-rays are likely to be produced via inverse Compton scattering of
near/mid IR photons emitted by the hot dust. We also infer that the largest
gamma-to-synchrotron luminosity ratio ever recorded in this object - having
taken place during its lowest luminosity states - can be simply due to weaker
magnetic fields carried by a less powerful jet.Comment: 19 pages, 3 figures, accepted for publication in Ap
Analysis of thermomechanical properties of polymeric materials produced by a 3D printing method
A comparative analysis of the thermomechanical properties of semicrystalline and amorphous polymeric materials was carried out. Samples were produced by using a 3D printing technology on the SIGNAL printer - ATMAT. The following polymeric materials were used to make the samples: TPU-thermoplastic polyurethane elastomer, ABS-copolymer acrylonitrile-butadiene-styrene, Nosewood, PET-ethylene terephthalate, PLA-poly (lactic acid). The research included a thermal analysis of the dynamic properties (DMTA) of manufactured materials
Late Palaeozoic strike-slip tectonics versus oroclinal bending at the SW outskirts of Baltica: case of the Variscan belt’s eastern end in Poland
Geophysical and geological data from the eastern sector of the Central European Variscan belt are presented and reviewed
in the regional tectonic context. Matched filtering of isostatic gravity, guided by results of spectral analysis, along with other
derivatives of gravity and magnetic fields reveal a dominant WNW–ESE-trending pre-Permian structural grain in the external
zones of the Variscan belt in Poland. This trend is confirmed by regional distribution of dips in Carboniferous and Devonian
strata that were penetrated by boreholes beneath Permian-Mesozoic sediments. Based on these data, two alternative concepts
explaining the connection of the Variscan belt and its NE foreland, those of strike-slip tectonics versus oroclinal bending,
are discussed. The WNW–ESE structural trend in the Variscan foreland is parallel to a set of major strike-slip fault zones in
the area, including those of Upper Elbe, Intra-Sudetic, Odra, Dolsk and Kraków-Lubliniec. These faults are considered to
convey a significant dextral displacement between Laurussia and Gondwana. The revised position of the Variscan deformation
front shows a similar, uninterrupted, generally WNW–ESE trend, up to the SE border of Poland, which indicates an
initial continuation of the Variscan belt into the area of the present-day Western Carpathians. The geometry of the Variscan
deformation front along with the pattern of the Variscan structural grain are inconsistent with the idea of an oroclinal loop
affecting the external, non-metamorphic Variscan belt. However, the data presented do not entirely rule out an oroclinal
loop within the Variscan internides. The still possible options are (1) a semi-oroclinal model postulating ~ 90° bending of
the Variscan tectonostratigraphic zones into parallelism with the WNW–ESE strike-slip faults or (2) an orocline limited only
to the belt linking the Wolsztyn High and Moravo-Silesian non- to weakly-metamorphic fold-and-thrust belt. Regardless of
the kinematic model preferred, our data indicate that structural evolution of the Polish Variscides was concluded with the
end-Carboniferous NNE–SSW shortening that resulted in the present-day extent of the Variscan deformation front
The shape of the Variscan Belt in Central Europe : strike-slip tectonics versus oroclinal bending
"The European Variscan belt sharply changes its trend in easternmost Germany and western
Poland, where the ENE- to NE-striking structures are replaced by the ESE- to SE-trending ones. The
structures of still another, NNE-SSW strike, take the lead, however, along the SE margin of the
Bohemian Massif. The Variscan belt seems, thus, to make nearly a U-turn, encircling the Bohemian
Massif from the north. This has been explained for almost a century by assuming a 180° oroclinal
loop, in which the Rhenohercynian and Saxothuringian tectonostratigraphic zones inarm the core
of the Bohemian Massif. According to this classical view, the outermost tectonostratigraphic zone
of the Variscan belt, the Rhenohercynian Zone, continues eastward in the deep substratum of the
Permian-Mesozoic basin and reappears at the surface along the eastern rim of the Bohemian
Massif." (fragm.
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