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Abstract

This paper describes the application of the skull melting method for an artificial generation of particulate material of inorganic compounds like CsOH, NaOH, SnO2 and UO2. The skull melting process is analyzed analytically. Thereby the electromagnetic field is calculated by a one dimensional time harmonic model. Thermal losses are estimated by simple analytical formulas. Finally an electromagnetic thermal field coupling is performed to calculate the temperature distribution inside the crucible, considering transient thermal effects. The skull melting process is simulated for the example of UO2. Under consideration of the given material properties it is shown that the skull melting method can be applied to fuse UO2.
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Authors and Affiliations

Björn Riemer
Enno Lange
Kay Hameyer
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Abstract

Voting power methodology offers insights to understand coalition building in collective decision making. This paper proposes a new measure of voting power inspired from Banzhaf (1965) accounting for the proximity between voters by capturing how often they appear in winning coalitions together. Using this proximity index, we introduce a notion of relative linkages among coalition participants as determinant of coalition building. We propose an application to the governance structure of the International Monetary Fund, with linkages being represented by bilateral volumes of trade between voters. The results are able to explain several important features of the functioning of this particular voting body, and may be useful for other applications in international politics.

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Authors and Affiliations

Julien Reynaud
Fabien Lange
Łukasz Gątarek
Christian Thimann
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Abstract

The connection of renewable energy sources with significant nominal power (in the order of MW) to the medium-voltage distribution grid affects the operating conditions of that grid. Due to the increasing number of installed renewable energy sources and the limited transmission capacity of medium-voltage networks, the cooperation of these energy sources is becoming increasingly important. This article presents the results of a six-year study on a 2 MW wind power plant and a 1 MW photovoltaic power plant in the province of Warmia and Mazury, which are located a few kilometers away from each other. In this study, active energy, currents, voltages as well as active, reactive, and apparent power and higher harmonics of currents and voltages were measured. The obtained results show the parameters determining the power quality at different load levels. Long-term analysis of the operation of these power plants in terms of the generated electricity and active power transmitted to the power grid facilitated estimating the repeatability of active energy production and the active power generated in individual months of the year and times of day by a wind power plant and a photovoltaic power plant. It also allowed us to assess the options of cooperation between these energy sources. It is important, not only from a technical but also from an economic point of view, to determine the nominal power of individual power plants connected to the same connection point. Therefore, the cooperation of two such power plants with the same nominal power of 2 MW was analyzed and the economic losses caused by a reduction in electricity production resulting from connection capacity were estimated.
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Authors and Affiliations

Andrzej Lange
1
ORCID: ORCID
Marian Pasko
2
Dariusz Grabowski
2
ORCID: ORCID

  1. Department of Electrical and Power Engineering, Electronics and Automation, University of Warmia and Mazury, ul. M. Oczapowskiego 11, 10-719 Olsztyn, Poland
  2. Department of Electrical Engineering and Computer Science, Silesian University of Technology, ul. Akademicka 10, 44-100 Gliwice, Poland
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Abstract

In this study, to investigate effects of tin addition on the microstructures and corrosion properties, Zn-1Mg-xSn (x = 1.0, 2.0 and 5.0 wt.%) ternary zinc alloys were prepared. The experimental results indicated that the Zn-1Mg-2.0 wt.% Sn alloy has the better mechanical properties compared with pure zinc and Zn-1Mg alloy. The tensile strength of the alloy material is 173.2±3.7 MPa, the yield strength is 120.7±2.4 MPa, the elongation is 5.64±0.08% and the hardness is 76.9±0.8 HV. The average degradation rate of the alloys immersion in SBF solution for 60 days is 0.16±0.03 mm/year, and the Zn-1Mg-2.0 wt.% Sn alloy hemolysis rate is only 0.81±0.02%. It is confirmed that the addition of tin is effective to improve the mechanical properties and degradation of Zn-1Mg alloy. It may be a candidate of the clinical application requirements of the degradable implant materials in orthopedics.
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Authors and Affiliations

Zhouling Long
1
ORCID: ORCID
Haiyang Lang
2
ORCID: ORCID
Jun Ou
2 3
ORCID: ORCID

  1. Materials Science and Engineering, Guilin University of Technology, China
  2. Guilin University of Technology, College of Materials Science and Engineering / Dental Clinic and Experimental Center of Medical Sciences, 12 Jianganroad, Guilin, 541004, Guilin, China
  3. Guilin Medical University, Experimental Center of Medical Sciences, 26, Huanchen Road Guilin, 541002, Guilin, China
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Abstract

This paper proposes a method to optimize reinforcement layout of three-dimensional members under a state of complex stress and multiple load cases (MLCs). To simulate three-dimensional members, the spatial truss-like material model is adopted. Three families of truss-like members along orthotropic directions are embedded continuously in concrete. The optimal reinforcement layout design is obtained by optimizing the member densities and orientations. The optimal design of three-dimensional member is carried out by solving the problem of minimum volume of reinforcing bars with stress constraints. Firstly, the optimized reinforcement layout under each single load case (SLC) is obtained as per the fully stressed criterion. Second, on the basis of the previous results, an equivalent multi-case optimization is proposed by introducing the idea of stiffness envelope. Finally, according to the characteristics of the truss-like material, a closed and symmetrical surface is adopted to fit the maximum directional stiffness under all SLCs. It can be proved that the densities and orientations of truss-like members are the eigenvalues and eigenvectors of the surface coefficient matrix, respectively. Several three-dimensional members are used as examples to demonstrate the capability of the proposed method in finding the best reinforcement layout design of each reinforced concrete (RC) member and to verify its efficiency in application to real design problems.
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Authors and Affiliations

Hao Cui
1
ORCID: ORCID
Junjie Xia
1
ORCID: ORCID
Lang Wu
1
ORCID: ORCID
Min Xiao
1
ORCID: ORCID

  1. College of Civil Engineering and Architecture, Jiangxi Science and Technology Norma lUniversity, No.605 Fenglin Avenue, 330013, Nanchang, China
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Abstract

Tests were performed on example tools applied in hot die forging processes. After withdrawal from service due to excessive wear, these tools can be regenerated for re-use through machining and hardfacing. First, analysis of worn tools was carried out for the purpose of identifying tool working conditions and wear mechanisms occurring in the surface layer of tools during forging. Testing of worn tools included observations under a microscope, surface scanning and microhardness measurement in the surface layer. The results indicate very diverse work conditions, which suggest the application of different materials and hardfacing tool regeneration technology in individual die forging processes.
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Authors and Affiliations

P. Widomski
1
ORCID: ORCID
M. Kaszuba
1
ORCID: ORCID
J. Krawczyk
1
ORCID: ORCID
B. Nowak
2
ORCID: ORCID
A. Lange
1
ORCID: ORCID
P. Sokołowski
1
ORCID: ORCID
Z. Gronostajski
1
ORCID: ORCID

  1. Wroclaw University of Science and Technology, Department of Metal Forming, Welding and Metrology, 7-9 Lukasiewicza Str., 50-371, Wroclaw, Poland
  2. CEO, Kuźnia Jawor S.A. Poland

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