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Number of results: 8
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Abstract

This paper presents the results of modeling and analysis of hybrid generation system (HSW). The system contains municipal waste gasification installation, photovoltaic (PV) system and wind farm. The system cooperates with the power system to provide electrical energy to the communal consumer. The consumer is characterized by a maximum power demand equal to 10 MW and an annual energy demand of 42.351 GWh. Generation with renewable sources was modelled using meteorological data. Moreover, in order to cover the demand with the level of generation, gas storage was used. Next, the three-stage gasification model is presented. It was validated, using the literature data, and its efficiency and gas composition have been calculated and are presented. Furthermore, energetic and economic analysis have been conducted. Installed power usage factor and efficiency of energy sources were calculated. Gross and net energy generation of hybrid generation systems have been computed and are presented. In this analysis, energy consumption by gas compressing was included. The analyzed HSW covered 54.5% of the demand. Most of this (30.2%) was covered by the gasification system. However, the system was characterized by a low net efficiency equal to 16.7%. Diagrams of power generation in each source and storage fill chart are presented. In the economic part of the analysis, results of calculations of net present value and payback period are published in order to examine the profitability of the system.
The cost of electricity was 490–1050 PLN/MWh. The results show that municipal waste gasification can be used as a part of HSW to adjust the generation with the demand. Moreover, it can be economically advantageous. However, it is characterized by high CO 2 emission and low efficiency of the waste processing system.
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Authors and Affiliations

Jacek Roman
1
ORCID: ORCID

  1. Institute of Electrical Power Engineering, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Poland
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Abstract

This article explores the experiences of lesbian, gay, bisexual and transgender (LGBT) migrants from Central and Eastern Europe and the Former Soviet Union in Scotland. Drawing on interviews with 50 migrants, the article focuses on the experiences and aspirations which they articulate as being part of ‘a normal life’, and analyses them within broader conceptual understandings of security and ‘normal-ity’. We first examine how normality is equated with an improved economic position in Scotland, and look at the ways in which this engenders feelings of emotional security and well-being. We then explore how more positive experiences around sexuality and gender identity are key to a sense of emotional security – i.e. of feeling accepted as ‘normal’, being visible as an LGBT person but ‘blending in’ rather than standing out because of it. Finally we look at the ways in which the institutional framework in Scotland, in particular the presence of LGBT-affirmative legislation, is seen by participants to have a normalising effect within society, leading to a broader sense of inclusion and equality – found, again, to directly impact upon participants’ own feelings of security and emotional well-being. The article engages with literatures on migration and sexuality and provides an original contribution to both: through its focus upon sexuality, which remains unexplored in debates on ‘normality’ and migration in the UK; and by bringing a migration perspective to the debates in sexuality studies around the normal-ising effect of the law across Europe. By bringing these two perspectives together, we reveal the inter-rela-tionship between sexuality and other key spheres of our participants’ lives in order to better understand their experiences of migration and settlement.

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Authors and Affiliations

Francesca Stella
Moya Flynn
Anna Gawlewicz
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Abstract

In order to find the defects in ferromagnetic materials, a non-contact harmonic detection method is proposed. According to the principle of frequency modulated carrier wave, a tunnel magneto resistance harmonic focusing vector array detector was designed which radiates lower and higher frequency electromagnetic waves through the coil array to the detection targets. We use bistable stochastic resonance to enhance the energy of collected weak target signal and apply quantum computation and a Sobol low deviation sequence to improve genetic algorithm performance. Then we use the orthogonal phase-locked loop to eliminate the intrinsic background excitation field and tensor calculations to fuse the vector array signal. The finite element model of array detector and the magnetic dipole harmonic numerical model were also established. The simulation results show that the target signal can be identified effectively, its focusing performance is improved by 2 times, and the average signal-to-noise ratio is improved by 9.6 times after the algorithm processing. For the experiments, we take Q235 steel pipeline as the object to realize the recognition of three defects. Compared with the traditional methods, the proposed method is more effective for ferromagnetic materials defects detection.
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Authors and Affiliations

Yizhen Zhao
1
Xinhua Wang
1
Yingchun Chen
1
Haiyang Ju
1
Yi Shuai
1

  1. Beijing University of Technology, College of Mechanical Engineering and Applied Electronics Technology, 100 Ping Le Yuan, Chaoyang District, Beijing 100124, China
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Abstract

A total of 704 fishes representing 39 species were examined. Twenty five digenean species were recognized. Only one species previously found by the present author in a fiord of this area was absent in the material. Pelagic species were usually not parasitized by digeneans, while demersal fishes were normally found to be infected. Results of the present study are compared to those from fiords. Seven species were found to be widely distributed. Two of them, Macvicaria pennelli and Genolinea bowersi, were associated with an inshore fiord environment and could be used as biological tags indicating the association of hosts with this kind of environment. Three of widely distributed species, Lepidapedon garrardi, Elytrophalloides oatesi and Lecilhaster macrocotyle, were not clearly associated with any environment.

Gonocerca phycidis, Neolebouria antarctica and other less widely distributed species, with the exception of Postmonorchis variabilis, were associated with deep part of fiords and/or open sea shelf environment. The level of infection of open sea fish at the South Shetlands was low. Many fish species living at South Georgia were massively infected; the dominant species in this area is E. oatesi, which was rare off the South Shetland Islands. A total of 45 digenean species occurring in the Antarctic fish were listed. Eleven of them were not endemic.

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Authors and Affiliations

Krzysztof Zdzitowiecki
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Abstract

Construction elements of supercritical power plants are subjected to high working pressures and high temperatures while operating. Under these conditions high stresses in the construction are created. In order to operate safely, it is important to monitor stresses, especially during start-up and shut-down processes. The maximum stresses in the construction elements should not exceed the allowable stress limit. The goal is to find optimum operating parameters that can assure safe heating and cooling processes [1-5]. The optimum parameters should guarantee that the allowable stresses are not exceeded and the entire process is conducted in the shortest time. In this work new numerical method for determining optimum working parameters is presented. Based on these parameters heating operations were conducted. Stresses were monitored during the entire processes. The results obtained were compared with the German boiler regulations - Technische Regeln für Dampfkessel 301.

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Authors and Affiliations

Piotr Duda
Dariusz Rząsa
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Abstract

Performance assessment of ejector-expansion vapor compression refrigeration system with eco-friendly R134a alternative refrigerants (R152a, R1234yf, R600a, R600, R290, R161, R32, and propylene) is presented for air-conditioning application. Ejector has been modeled by considering experimental data based correlations of component efficiencies to take care of all irreversibilities. Ejector area ratio has been optimized based on maximum coefficient of performance (COP) for typical air-conditioner operating temperatures. Selected refrigerants have been compared based on area ratio, pressure lift ratio, entrainment ratio, COP, COP improvement and volumetric cooling capacity. Effects of normal boiling point and critical point on the performances have been studied as well. Using ejector as an expansion device, maximum improvement in COP is noted in R1234yf (10.1%), which reduces the COP deviation with R134a (4.5% less in basic cycle and 2.5% less in ejector cycle). Hence, R1234yf seems to be best alternative for ejector expansion system due to its mild flammability and comparable volumetric capacity and cooling COP. refrigerant R161 is superior to R134a in terms of both COP and volumetric cooling capacity, although may be restricted for low capacity application due to its flammability.

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Authors and Affiliations

Shubham Mishra
Jahar Sarkar
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Abstract

The Compendium of Polish Medals is the first work on the history of Polish medallic art. The summary of work’s creation process, its assumptions and methodology together with opinions of readers and posterity have been presented below.

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Authors and Affiliations

Maria Stahr
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Abstract

The article presents the roots of contemporary Jewish-Polish relations in Poland. The Author analyses various phenomena and processes, leading to initiation of the Polish-Jewish dialogue in the years 1979- -1997, as well as evaluates the mutual relations between the two social groups in the turn of 1980s to 1990s.
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Authors and Affiliations

Katarzyna Paszko

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