Modeling of a supercritical power plant with an oxy type pulverized fuel boiler, a carbon dioxide capture unit and a ‘four-end’ type membrane air separator

The analysis of a 600 MW supercritical power plant with parameters of life steam at 30 MPa/ /650o C and of reheated steam 6 MPa/670o C was made. Power plant is equipped with the following units: oxy type pulverized fuel boiler, ‘four-end’ high temperature membrane air separator and carbon dioxide capture system which were modeled. With the assumption of a constant gross power of the analyzed power plant, the thermal efficiency of the boiler and the steam cycle efficiency were calculated. These parameters were designated as a function of the recovery rate of oxygen in the air separation unit. This allowed to determine gross and net efficiency of electricity generation

The characteristics of a modern oxy-fuel power plant

This paper presents the thermodynamic and economic analyses of four variants of a supercritical oxy-type plant. These variants differed in terms of air separation units (ASU, variants: V1—cryogenic; V2—hybrid; equipped with a three-end (V3a) or four-end (V3b) high-temperature membrane) and boilers (V1 and V3a—lignite-fired fluidized-bed; V2 and V3b—hard-coal-fired pulverized-fuel). The gross power of steam turbine unit (STU) was 600 MW. The live and reheated steam parameters were 650 °C/30 MPa and 670 °C/6.5 MPa, respectively. The influence of the ASUs’ operating parameters on the ASUs’ auxiliary power rate and boiler efficiency (V3a and V3b only) was studied. The ASUs’ operating parameters for maximum net efficiency were then determined. The decrease in the net efficiency compared to a reference plant (with a classic fluidized-bed or pulverized-fuel boiler) fluctuated in the range 7.2 (V3b)–11.2 (V1) p.p. An analysis of the waste heat utilization was performed (fuel drying—V1 and V3a; STU steam-water heat exchangers replacing). Thus, the efficiency decreases fluctuated in the range 4.3 (V3b)–10.2 (V1) p.p. The economic analysis showed that in order for the variants to be economically viable, the unit CO2 emission cost should be greater than 42.2 (V1) or 22.0 (V3b) EUR/MgCO2

Rocznik Lubuski (t. 31, cz.1): Muzea i ochrona dziedzictwa kulturowego na Środkowym Nadodrzu

Muzea i Ochrona Dziedzictwa Kulturowego na Środkowym Nadodrzu

La débat de Stanislaw Mendelson et de Karl Marx sur la dictature du prolétariat

Il existe toujours le débat sur l'essentiel de la dictature du prolétariat. Il a été entamé au debut de notre siècle par le travail d'Eduard Bernstein intitulé Les principes du socialisme el les taches du socialisme social. On opposait le phénomène de la Commune de Paris dont l'essentiel a été décrit par Karl Marx dans guerre civile en France à l’opinion que la dictature du prolétariat n'est pas réalisable. Le opint de vue de Marx sur la Commune de Paris été nié par Stanisław Mendel son dans son travail paru en 1904: L'histoire du mouvement communiste en France en 1871. Mendelson fait la critique de l'affirmation de Karl Marx que la Commune de Paris costituait „par son essentiel un pouvoir exercé par la classe ouvrière, le résultat de la lutte des producteurs et des expropriateurs". Cette lutte a été pour Mendelson „la lutte des masses démocratiques de la capitale de la France contre la réaction, la lutte qui perdait le caractère de la lutte des classes, la lutte qui ne relevait pas uniquement de l'histoire du prolétariat mais qui est devenu un episode de l'histoire de la liberté".Zadanie pt. Digitalizacja i udostępnienie w Cyfrowym Repozytorium Uniwersytetu Łódzkiego kolekcji czasopism naukowych wydawanych przez Uniwersytet Łódzki nr 885/P-DUN/2014 zostało dofinansowane ze środków MNiSW w ramach działalności upowszechniającej naukę

REASONING WITH MISSING, NOT-APPLICABLE AND IRRELEVANT

Title: Reasoning with missing, not-applicable and irrelevant meta-value

Reasoning with Meta-values in AQ Learning

This paper describes methods for reasoning with missing, irrelevant and not applicable meta-values in the AQ attributional rule learning. The methods address issues of handling these values in datasets both for rule learning and rule testing. In rule learning, the presence of these values affects the extension-against generalization operator in star generation, and the rule matching operator. In rule testing, these values affect the execution of the rule matching operator. The presented methods have been implemented in the AQ21 learning program and tested on four datasets

The LEM3 System for Non-Darwinian Evolutionary Computation and Its Application to Complex Function Optimization

LEM3 is the newest implementation of Learnable Evolution Model (LEM), a non-Darwinian evolutionary computation methodology that employs machine learning to guide evolutionary processes. Due to a deep integration of different modes of operation and the use of the advanced machine learning system AQ21, the LEM3 system is a highly efficient and effective implementation of the methodology. LEM3 supports different attribute types for describing individuals in the population, such as nominal, rank, structured, interval and ratio, which makes it applicable to a wide range of practical problems. It also implements very efficient methods for switching between different modes of operation and operators controlling the generation of new individuals. This paper describes the underlying LEM3 algorithm, results from LEM3 testing on selected benchmark function optimization problems (with the number of variables varying from 10 to 1000), and its comparison with EA, a conventional, Darwinian-type evolutionary computation program. In every experiment, without exception, LEM3 outperformed EA in terms of the evolution length (the number of fitness evaluations needed to achieved a desired solution), sometimes very significantly. It also outperformed the previous LEM2 implementation