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Number of results: 15
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Abstract

Accurate understanding of the three-dimensional (3D) morphology of a complex goaf and its relative displacement in space is a precondition to further analyzing the stability of the cavity. In this study, to make an accurate stability analysis of the goaf, laser detection and numerical simulation are used to study the interior space form of goaf and the change characteristics of stress and displacement in goaf. The results of the study show that the BLSS-PE mining 3D laser system as a field detection tool can detect the morphology of the cavity more comprehensively and improve the accuracy of the detection data to a certain extent. Combined with the numerical simulation software analysis, it can be seen that the maximum principal stress in the 818-2# goaf increases after excavation. In addition, the maximum value appears in the top and bottom plates of the goaf, and the minimum stress remains nearly unchanged. The tensile stress appears in the upper and lower plates but is lower than the surrounding rock. The maximum horizontal and vertical displacements of the 818-2# goaf are small. The plastic zone appears in the surrounding rock of the goaf as the mining work progresses, but the area is small. It is concluded that the goaf is relatively stable overall. The research results may provide a strong reference for ground pressure management in mines and comprehensive control of goaves.
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Authors and Affiliations

Gangyou Sun
1
ORCID: ORCID
Yuandi Xia
2
ORCID: ORCID
Qinrong Kang
2
ORCID: ORCID
Weizhong Zhang
2
ORCID: ORCID
Qingzhen Hu
2
ORCID: ORCID
Wei Yuan
2
ORCID: ORCID

  1. The Fourth Research and Design Engineering Corporat ion, China
  2. School of Resources and Safety Engineering, Wuhan Institute of Technology, China
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Abstract

The article is based on the assumption that discourse plays a key role in constructing social reality. This also applies to ableism, i.e. discrimination against people with disabilities: the forms used to talk about this phenomenon shape its image and real relations within society. Inclusive language represents an attempt to counter ableism at the level of discourse. This text aims to analyze selected lexical units of Italian considered inclusive and demonstrate their weaknesses in preventing the exclusion of people with disabilities.
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Authors and Affiliations

Kamila Miłkowska-Samul
1
ORCID: ORCID

  1. Uniwersytet Warszawski
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Abstract

The size and distribution of water demand within a given structural unit is the basis for the proper operation and planning of the expansion and modernization of the water supply system’s elements. In rural areas, particularly in municipalities adjacent to urban-industrial agglomerations, a change in the use of tap water has been increasingly observed. The water consumption for animal breeding or agricultural use, typical of these areas, has been decreasing and even disappearing. Water has been increasingly used for domestic purposes in single- and multi-family housing as well as for other purposes such as watering lawns and filling residential swimming pools. Taking this into account, this paper presents observations regarding daily water consumption in a municipality adjacent to Wrocław together with an analysis of the possibility of using the exponential smoothing method for the short-term forecasting of daily water consumption. The analyses presented in this paper were carried out using STATISTICA 13 software.
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Authors and Affiliations

Wojciech Cieżak
1
ORCID: ORCID
Małgorzata Kutyłowska
1
ORCID: ORCID

  1. Wrocław University of Science and Technology, Faculty of Environmental Engineering, Wybrzeze Wyspianskiego 27, 50-370 Wrocław, Poland
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Abstract

The present article provides information on the method of distinguishing between spatial natural units within a valley microregion in the Arctic zone. Geocomplexes fall into 20 types and are grouped under four categories of high order units, i.e. glacial, fluvial, slope and polygenetic geocomplexes. The lithomorphogenetic criterion is useful in differentiating other natural characteristics.

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Authors and Affiliations

Andrzej Mizgajski
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Abstract

Sound propagation from the vehicles moving on the city roundabout, with taking into account the wind is investigated. Solution of the problem for one moving sound source is found by means of the integral Fourier transforms extended over space variables and time. Inverse transforms are calculated approximately, using a stationary phase method and iterative technique. The solution for a general problem is obtained as a superposition of many partial solutions. The numerical analysis of noise characteristics is performed for the three-way Korfanty roundabout case in Łódź.

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Authors and Affiliations

Olexa Piddubniak
Nadia Piddubniak
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Abstract

When we look at the history of AGH – University of Science and Technology, recognized as one of the best universities in the country, we find that for that success many people worked for several dozen years. However, the subjects, the methodology and directions of their work were shaped by units – outstanding personalities of science. Just to mention, among others Professors Stanisław Zuber, Władysław Takliński, Witold Budryk, Maksymilian Tytus Huber and Władysław Bogusz. These people have shaped our institution, marked its new path of development and permanent place in the history of Polish and world science. To belong to such a group is a great ennoblement, for which one works out for his entire life. Undoubtedly, such personality was also Professor Zbigniew Witold Engel, to whom we said goodbye on November, 6th, 2013, in the St. Clement’s church in Wieliczka. Professor was born on April 1, 1933, in Zawady near Zhovkva in the province of Lviv. After graduating from Jan Matejko Middle and High School in Wieliczka in 1950 earned a matriculation certificate. Then he began his studies at the Department of Communications of Polytechnic Departments of Academy of Mining and Metallurgy and involved with our university for the next 63 years. October 1, 1952 the Department of Mechanics of the University of Mining and Metallurgy was created, and soon after began professor’s adventure that was the work of science, education and organization. The history and fate of our university are inextricably linked with the person of professor who practically since the very beginning of the Faculty supported it in all areas of its activities, and has always actively participated in academic life.
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Authors and Affiliations

Jan Adamczyk
Wojciech Batko
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Abstract

Results are presented concerning the separation of the mixtures of carbon dioxide, nitrogen and oxygen in membrane modules with modified polysulphone or polyimide as active layers. The feed gas was a mixture with composition corresponding to that of a stream leaving stage 1 of a hybrid adsorptivemembrane process for the removal of CO2 from dry flue gas. In gas streams containing 70 vol.% of CO2, O2 content was varied between 0 and 5 vol.%. It is found that the presence of oxygen in the feed gas lowers the purity of the product CO2 in all the modules studied, while the recovery depends on the module. In the PRISM module (Air Products) an increase in O2 feed concentration, for the maximum permeate purity, led to a rise in CO2 recovery, whereas for the UBE modules the recovery did not change.

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Authors and Affiliations

Manfred Jaschik
Marek Tańczyk
Aleksandra Janusz-Cygan
Artur Wojdyła
Krzysztof Warmuziński
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Abstract

Thermodynamic descriptions of the ternary Fe-B-V system and its binary sub-system B-V, are developed using experimental thermodynamic and phase equilibrium data from the literature. The thermodynamic parameters of the other binaries, Fe-V and Fe-B, are taken from earlier assessments slightly modifying the Fe-V description. The work is in the context of a new Fe-B-X (X = Cr, Ni, Mn, V, Si, Ti, C) database.

The solution phases are described using substitutional solution model. The borides are treated as stoichiometric or semi-stoichiometric phases and described with two-sublattice models.

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Authors and Affiliations

J. Miettinen
V.-V. Visuri
T. Fabritius
N. Milcheva
G. Vassilev
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Abstract

This work concerns measurements of the radiant intensity emitted by LEDs. The influence of selected factors and parameters on the final measurement result are discussed. The research was conducted using two type of detectors: light meter and CCD camera, to compare the degree of influence of these parameters depending on the measurement instrument used.

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Authors and Affiliations

Joanna Parzych
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Abstract

This paper presents an elasticity solution of adhesive tubular joints in laminated composites, with axial symmetry. In this model, adherends are orthotropic shells and the stacking sequences can be either symmetric or asymmetric. Adhesive layer is homogenous and made of isotropic material. They are modelled as continuously distributed tension/compression and shear springs. Employing constitutive, kinematics and equilibrium equations, sets of differential equations for each inside and outside of overlap zones are obtained. By solving these equations, shear and peel stresses in adhesive layer(s), as well as deflections, stress resultants and moment resultants in the adherends are determined. It is seen that the magnitude of peel stresses due to transverse shear stress resultant is much greater than that obtained from axial stress resultant. The developed results are compared with those obtained by finite element analysis using ANSYS software. The comparisons demonstrate the accuracy and effectiveness of the aforementioned methods.
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Authors and Affiliations

Ehsan Selahi
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Abstract

In post-humanist studies of identity, otherness and exclusion – conducted within the de-anthropocentrism of the humanities – questions arise about the condition of non-human subjects (animals, plants, things) that gain the cultural and social status of Others. As non-human entities, they have a socializing value, cement interpersonal relations, attract people to certain places. They have performative, integrative and co-creating abilities. The posthumanistic “turn towards things” opens the room for the construction of their social (auto) biographies, a development which already has been taking place in contemporary children’s literature. The problem of the creation of (auto)biographies of non-human subjects is presented in this article on the example of the picture book Otto: The Autobiography of a Teddy Bear by Tomi Ungerer. The artist gives the non-anthropomorphized plush toy the status of a non-human subject and an active actor of social life as a medium of unoffi cial memory of the Holocaust. Ungerer consciously and innovatively uses the key determinants of the posthuman discourse, including intimate childhood experiences.

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Authors and Affiliations

Katarzyna Slany
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Abstract

Textural properties and microstructures are commonly used properties in the analysis of Pleistocene and older glacial deposits. However, contemporary glacial deposits are seldom studied, particularly in the context of post-depositional changes. This paper presents the results of a micromorphological study of recently deposited tills in the marginal zones of Hansbreen and Torellbreen, glaciers in southwestern Spitsbergen. The main objectives of this study were to compare modern tills deposited in subglacial and supraglacial conditions, as well as tills that were freshly released from ice with those laid down several decades ago. The investigated tills are primarily composed of large clasts of metamorphic rocks and represent coarse-grained, matrix-supported diamictons. The tills reveal several characteristic features for ductile (e.g. turbate structures) and brittle (e.g. lineations, microshears) deformations, which have been considered to be indicative of subglacial conditions. In supraglacial tills, the same structures are common as in the subglacial deposits, which points to the preservation of the primary features, though the sediment was transferred up to the glacier surface due to basal ice layer deformation and redeposited as slumps, or to formation of similar structures due to short-distance sediment re-deposition by mass flows. This study revealed that it might not be possible to distinguish subglacial and supraglacial tills on the basis of micromorphology if the latter are derived from a subglacial position. The only noted difference was the presence of iron oxide cementation zones and carbonate dissolution features in supraglacial tills. These features were found in tills that were deposited at least a few years ago and are interpreted to be induced by early post-depositional processes involving porewater/sediment interactions.
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Authors and Affiliations

Grzegorz Rachlewicz
Katarzyna Skolasińska
Witold Szczuciński

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