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Number of results: 19
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Abstract

Niniejsza publikacja przedstawia metodykę DEA jako narzędzie do oceny efektywności technologii energetycznych. W pierwszej części pracy ukazano podstawowe narzędzia wykorzystywane do oceny portfela projektów inwestycyjnych w przemyśle energetycznym. W dalszej części scharakteryzowano metody Data Envelopment Analysis (DEA), czyli nieparametryczne procedury ustalania efektywności technologicznej badanych obiektów pod względem analizowanych czynników. W części praktycznej – wykorzystując analizę DEA – dokonano przykładowej oceny efektywności trzynastu technologii energetycznych, w tym technologii nadkrytycznego spalania węgla, zgazowania węgla połączonego z turbiną gazową oraz samodzielnego układu turbiny gazowej. Do analizy wykorzystano model nadefektywności nieradialnej z uwzględnieniem podziału na nakłady decyzyjne, niedecyzyjne oraz produkty pożądane i niepożądane. Dodatkowo przeprowadzona została analiza wyników dla przykładowej technologii. Zostały wytłumaczone możliwe sposoby interpretacji wyników końcowych z punktu widzenia obiektów efektywnych, jak i nieefektywnych. W tym drugim przypadku przedstawiono także kalkulację rozwiązania wzorcowego dla danej instalacji wraz z wnioskami co do skali działalności.
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Abstract

Since 1978 the retreat of Ecology Glacier in the vicinity of Henryk Arctowski Station has opened new ice-free areas for colonization by terrestrial organisms initiated by pioneer microbes. Samples were collected from the soil surface, at 0, 5 and 20 cm below surface close to glacier front, then stored at below -20°C . Total bacterial count (TC), estimated by epifluorescence microscopy, reached high values, of 1010 g-1 dry wt. Healthy looking bacterial cells of mean volume 0.0209 µm3 at 0 cm to 0.0292 µm3 at 20 cm made up from 7% at 0 cm , to 30% at 20 cm of total bacterial population. The number of colony forming units (CFU) accounted for only 0.02% of TC. Taxonomically they belonged to the a, b, g subdivisions of the proteobacteria and to the Cytophaga-Flavobacterium-Bacteroides (CFB) group. Morphophysiologically CFU bacteria were diverse, from Gram variable short coccal forms to very long rods or filaments. Randomly selected CFU colonies were characterized by low sugar assimilation and high esterase/lipase activity. Spore forming bacteria – absent from 0 and 5 cm , formed a small fraction of 175 cells g-1 dry wt at the 20 cm depth. Filamentous fungi were relatively abundant and represented mainly by oligotrophs.
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Abstract

In this paper an artificial neural network, which realizes a nonlinear adaptive control algorithm, has been applied in a control system of variable speed generating system. The speed is adjusted automatically as a function of load power demand. The controller employs a single layer neural network to estimate the unknown plant nonlinearities online. Optimization of the controller is difficult because the plant is nonlinear and no stationary. Furthermore, it deals with the situation where the plant becomes uncontrollable without any restrictive assumptions. In contrast to previous work [1] on the same subject, the number of neural networks has been reduced to only one network. The number of the neurons in a network structure as well as choosing certain design parameters was specified a priori. The computer test results have been presented to show performance of proposed neural controller.
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Abstract

This publication presents an assessment of the economic efficiency of a hypothetical installation for the gasification of the municipal and industrial waste for the production of syngas used subsequently for the production of energy or chemical products. The first part of the work presents an example of a technological system for the energo-chemical processing of coal mud and municipal waste, based on the gasification process using a fluidized bed reactor. A hypothetical installation consists of two main blocks: a fuel preparation unit and a gasification unit. In the fuel preparation installation, reception operations take place, storage, and then grinding, mixing, drying and transporting fuel to the gasification unit. In the gasification installation, fuel gasification, oxygen production, cooling and purification of raw process gas and ash treatment are carried out. The following key assumptions regarding the gasification process, as well as the capital expenditures and operating costs related to the process, were estimated. Consequently, based on the method of discounted cash flows, the unit cost of generating energy contained in the synthesis gas (cost of energy, COE) was determined and the results were interpreted. In order to obtain an acceptable efficiency of the gasification process for waste fuels for the production of alternative fuel (process gas), it is necessary to supplement the mixture of waste coal and coal mud with the RDF. In this case, the unit cost of fuel measured by the PLN/GJ index is lower than in the case of hard coal and comparable with brown coal. The use of coal mud for the production of process gas in an economically efficient way is possible only in the case of changes in the legal system allowing for charging fees for the utilization of industrial waste – coal mud.
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Abstract

Abstract A chlorophyll fluorescence technique enabled early detection of disturbances in the activity of the photosynthet-ic apparatus under Phoma lingam infection. The photosynthetic apparatus of leaves and cotyledons exhibited a negative response to P. lingam inoculation. The effect disappeared more rapidly in leaves, which were not inoculated directly, than in cotyledons, which were inoculated directly. Photosynthetic apparatus disturbances were detected in cotyledons and leaves as early as 24 h after inoculation. Photosynthetic apparatus activity can be affected by the level of hydrogen peroxide, which in cotyledons probably was an element of the hypersensitive response and in leaves could induce an increase in pathogenesis-related proteins, chitinase and β-1,3-glucanase.
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