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Abstract

This study presents a fuzzy analytic hierarchy process (FAHP) by integrating analytic hierarchy process (AHP) and fuzzy cognition to evaluate the construction risks of tunnel portals. Wuguanyi Tunnel is taken as the research objective to validate the performance of the proposed method. The result shows that the proposed decision making method can effectively identify risk factors and determine the risk level during the construction of tunnel portals. Finally, the corresponding control measures during the construction of the Wuguanyi Tunnel portal are proposed according to the risk assessment results.

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Authors and Affiliations

Xianghui Deng
ORCID: ORCID
Rui Wang
ORCID: ORCID
Tian Xu
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Abstract

The paper presents the most frequently encountered types and mechanism of damage of turbines' flow elements. The methods used nowadays for diagnosis of the damage are presented. A new possibility of localisation of damaged areas of turbine blades based upon the analysis of isotherm layout is proposed.
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Authors and Affiliations

Jerzy Madej
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Abstract

To improve the mechanical properties of casting aluminum-copper alloy, the mixed rare earth (RE) was added to ZL206 and its properties and the enhanced mechanism of alloy were researched. The results showed that the strength and hardness of the composite were improved by 10.2% and 6.2%, respectively. After adding mixed RE, which was led by the heterogeneous enrichment area blocking the growth of the α-Al phase and making grain refinement during the solidification process. The simulation results of RE surface adsorption models by first principles also showed that the elastic constant calculation improved the bulk modulus, shear modulus, and Young's modulus of the material. The addition of mixed RE enhances the strength and hardness, although it adversely affects toughness and reduces the machining index. Also, the work function decreased, and the Fermi level increased, reflecting that the electron locality on each band was strong and the bonding state of the alloy system was covalent, which showed that the corrosion resistance was enhanced after adding mixed RE. It provides a new method for the mechanism of RE-modified aluminum-copper alloys and expands the direction of cast aluminum-copper alloy modification.
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Authors and Affiliations

Xin Li
1
ORCID: ORCID
Medetbek Uulu Nurtilek
1
Ziqi Zhang
1
Lixia Wang
1
Quan Wu
1
Peixuan Mao
1
Rong Li
1
ORCID: ORCID

  1. School of Mechanical & Electrical Engineering, Guizhou Normal University, China
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Abstract

In contrast to the western part of the Lower Silesia, information about the basalt-derived weathering crusts occurring in the Opole region is rather limited. However, in 2018, significant volumes of such regolith (about 20,000 m3) were discovered during development works in the NW part of the Rutki Quarry near Niemodlin. This weathering crust is rich in clay minerals and represents a smectite- kaolinite mixture with some halloysite, the latter being a poorly ordered member of the kaolinite group. The minerals of the smectite group contain in their interlayer spaces bivalent cations (calcium and magnesium), which is the most often case in the nature. The mineral composition of the regolith mass is supplemented by iron-containing phases, i.e. goethite and magnetite, and traces of phosphate mineral – crandallite. A significant amount of clay minerals, particularly those belonging to the smectite group and halloysite, results in high value of the specific surface area (up to 100 m2/g) of the studied crust. Such favorable property of the crust makes it a promising sorptive raw material that can be applied, even in an unprocessed form, for waterproofing. It must be emphasized that the sorption properties of basalt weathering crusts were noticed some centuries ago in the western part of Lower Silesia, where medicine called terra sigillata was produced from them. Moreover, the crust from Rutki was also used in the XIXth century, in a ceramic manufacture located in nearby Tułowice, where the so-called “Silesian black porcelain” was produced.
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Authors and Affiliations

Piotr Wyszomirski
1
ORCID: ORCID
Tadeusz Szydłak
1
ORCID: ORCID
Tomasz Zawadzki
2
Marcin Baranowski
2

  1. AGH University of Krakow, Poland
  2. Kopalnie Odkrywkowe Surowców Drogowych SA, Niemodlin, Poland
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Abstract

Remarkable contemporary Lebanese artist Akram Zaatari reveals a complicated post-war situation of multicultural society of the Middle East in the context of the Ottoman Empire. He compares his conceptual artistic practice to the work of the archaeologist on excavations. Being the artist-as-archivist, he recalls the European humanism in the heroic version of existentialism.
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Authors and Affiliations

Zofia Chojnacka
1
ORCID: ORCID

  1. Instytut Sztuki PAN
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Abstract

The objective of this project was to evaluate and measure the viewability of various kinds of ads in the daily press. A total of 63 ads was assessed, including 17 in Metrocafe, 28 in Gazeta Wyborcza, and 18 in the Super Express. The analysis of the data made it possible to assess the effectiveness of various formats of press advertising.

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Authors and Affiliations

Barbara Kiljańska
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Abstract

Lessing’s question about knowing God (the Absolute) in history has been a con-stant challenge for modern theology. The article collates views of Joseph Ratzinger and Walter Kasper on this subject. A clear difference was noticed: Kasper decidedly gives priority to history and revelation in it, whereas Ratzinger puts stress on the idea of the priority of God and in its light interprets revelation and history. Two different types of theology emerge here. They manifest themselves in different ways of present-ing Christology. The former originates from the historical witness to Jesus and on this basis strives to construct a coherent picture of the incarnated Son of God’s identity. The latter originates from – resulting from the Church’s faith – an assumption about the unity of the Scripture and presents in this light the witness of the Gospel to Jesus. A thesis is proposed that both types of theology need each other, although it is not possible to harmonize them.

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Authors and Affiliations

Ks. Jacek Kempa
ORCID: ORCID

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