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Number of results: 6
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Abstract

In 2008, the European Union adopted the climate and energy package. It foresees the three most important goals to achieve by 2020 in the field of energy: 20% reduction in greenhouse gas emissions, 20% share of energy from renewable sources in total energy consumption in the EU, 20% increase in EU energy efficiency. Therefore, individual countries were obliged to move away from fossil fuels for renewable energy production. Depending on the capabilities of each country and the development of renewable energy, various goals have been set for individual countries. For Poland, the share of RES energy in total energy consumption has been set at 15% (Directive 2009). The Polish energy policy until 2030 includes state strategies in the field of implementation of tasks and objectives in the area of energy resulting from the need to build national security and EU regulation. The challenges of the current national energy industry include increasing demand for energy and implementation of international commitments in the area of environmental and climate protection (Policy 2009). Contemporary domestic energy is characterized by a high share of fossil fuels, mainly coal, in the production of electricity and heat, and the different share of RES energy in individual technologies and energy sectors. Poland has significant natural resources, which are a source of biomass for energy purposes. Large energy units dominate in the national consumption of biomass while the share of heating plants is still insignificant (Olsztyńska 2018). The aim of the article is to analyze, based on available data and own observations of the author, the share of biomass in the national energy and heat, as well as defining factors affecting the level of biomass use in the area of Polish power industry.

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Authors and Affiliations

Ilona Olsztyńska
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Abstract

The article presents the possibility of using the Cobb-Douglas production function for planning in a turbulent environment. A case study was carried out – the Cobb-Douglas function was used to examine the condition of the Polish hard coal mining industry and the progress which has been made after undertaking certain activities aimed at increasing the competitiveness of coal companies over recent years. Only the correct and confirmed identification of the causes of irregularities in the production process can allow for the introduction of effective remedies. The effectiveness of the solutions proposed by the author has been confirmed thanks to the simulation during which the impact of the proposed production strategy on the parameters of the CD function was examined. Three variants of production functions models were created and production productivity rates and marginal substitution rates were determined. The results enabled the verification of the progress of restructuring as well as identification of the origin of the observed problems and comparison of the current state with the results of analyses carried out in previous years. Scenarios of possible trend developments for the factors introduced into the function model in order to present remedial measures that could improve the process of hard coal extraction were created. The scenarios were created using the ARIMA class models. Which scenario is the most favourable was determined. A computer program, created by the author, for optimising the level and use of labor resources at the level of the entire coal company has been presented.

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Authors and Affiliations

Aurelia Rybak
ORCID: ORCID
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Abstract

The experiment conducted with the NOKIA Multigraph 447Xpro presented in this article shows that a change of colour temperature results in a change of general colour appearance displayed on the CRT screen. However, it does not considerable affect chromatic coordinates of RGB monitor primary stimuli. The change of :a produced colour appearance which it causes can have a considerable influence on colour matching - at tłie stage of map designing on the screen. Discordances among given colour temperature set-up in lhe screen menu in relation to computed by means measurements of colour temperature are shown. Of computing and Methods of colour temperature calculating and setting are given. It has been stated which channel has a critical (decisive) influence on a colour temperature setup.
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Authors and Affiliations

Joanna Puszkarska
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Abstract

The present work comprises a numerical analysis using the Ansys program to solve the problem of combined free-forced convection around a circular cylinder located in a horizontal lid-driven trapezoidal enclosure. The enclosure is filled with water. The upper moving wall and lower fixed wall are cold at a constant temperature, whereas the inclined walls are adiabatically insulated. The uniformly heated cylinder is located at different positions in the cavity. The study covers three values of Richardson number (0.01, 1, and 10). The results show that the streamlines and isotherms in the enclosure, the Nusselt number and friction factor in the moving wall, hot wall and bottom wall are strongly dependent on the position of the inner hot cylinder. The results are validated with previous work, and the comparison gives good agreement.
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Authors and Affiliations

Asmaa Ali Hussein
1

  1. Middle Technical University, Institute of Technology/Baghdad, Baghdad, Iraq
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Abstract

At present, with the increase of production capacity and the promotion of production, the reserves

of most mining enterprises under the original industrial indexes are rapidly consumed, and the full

use of low-grade resources is getting more and more attention. If mining enterprises want to make

full use of low-grade resources simultaneously and obtain good economic benefits to strengthening

the analysis and management of costs is necessary. For metal underground mines, with the gradual

implementation of exploration and mining projects, capital investment and labor consumption are

dynamic and increase cumulatively in stages. Consequently, in the evaluation of ore value, we should

proceed from a series of processes such as: exploration, mining, processing and the smelting of

geological resources, and then study the resources increment in different stages of production and the

processing. To achieve a phased assessment of the ore value and fine evaluation of the cost, based on

the value chain theory and referring to the modeling method of computer integrated manufacturing

open system architecture (CIMOSA), the analysis framework of gold mining enterprise value chain is

established based on the value chain theory from the three dimensions of value-added activities, value

subjects and value carriers. A value chain model using ore flow as the carrying body is built based on

Petri nets. With the CPN Tools emulation tool, the cycle simulation of the model is carry out by the

colored Petri nets, which contain a hierarchical structure. Taking a large-scale gold mining enterprise

as an example, the value chain model is quantified to simulate the ore value formation, flow, transmission

and implementation process. By analyzing the results of the simulation, the ore value at different

production stages is evaluated dynamically, and the cost is similarly analyzed in stages, which can improve mining enterprise cost management, promote the application of computer modeling and

simulation technology in mine engineering, more accurately evaluate the economic feasibility of ore

utilization, and provide the basis for the value evaluation and effective utilization of low-grade ores.

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Authors and Affiliations

Zhaoyang Ma
Nailian Hu
Guoqing Li
Di Liu
Tao Pan
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Abstract

Baudelaire’s Catholicism seems difficult to interpret, therefore some authors declare the poet a Satanist. In my opinion, this is rather problematic to call Charles Baudelaire a Satanist. It is very debatable and doubtful, but there are several reasons for this. In the collection of poetry entitled “Les Fleurs du mal” (“The Flowers of Evil”), Baudelaire gave a voice to the Devil many times. He wrote a scandalous poem “Litanies de Satan” (“The Litany of Satan”). In fact, Satan tempts us and leads us, after all he is closer to man that God! Was Baudelaire a Satanist? It is question to be answered.

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Authors and Affiliations

Jan Tomkowski

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