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Number of results: 100
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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

A mine cannot function without monitoring systems: environmental, basic mining machinery and equipment. The exploitation of ore in the mine depends heavily on properly functioning machines and mining equipment, and acceptable for the miner technical environmental conditions occurring in underground excavations. The monitoring systems of the technical environment in underground mines are primarily telemetry and gasometry systems. The first part of the article shows the typical structure of gasometry systems operating in the Polish underground mines. The existing provisions include the so-called security systems of the mining plant. The article presents a quantitative summary of the telephone exchange types and count of main telecommunication lines operating in these systems. Monitoring systems of machines and mining equipment are an essential element of the effec-tive management of the mine, because they affect the safe operation and increase time of effi-ciency equipment. The second part of the article shows selected monitoring systems of mining machinery and equipment currently used in the dispatcher rooms of mines. Attention was paid to the monitoring systems, which are only software tools as well as those in which additionally use dedicated IT solutions for these systems, hardware and measuring tools. The table shows the types of monitoring systems and technological configurations used in underground mines, preferred for them.
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Abstract

Increasing the share of energy production from renewable sources (RES) plays a key role in the sustainable and more competitive development of the energy sector. Among the renewable energy sources, the greatest increase can be observed in the case of solar and wind power generation. It should be noted that RES are an increasingly important elements of the power systems and that their share in energy production will continue to rise. On the other hand the development of variable generation sources (wind and solar energy) poses a serious challenge for power systems as operators of unconventional power plants are unable to provide information about the forecasted production level and the energy generated in a given period is sometimes higher than the demand for energy in all of the power systems. Therefore, with the development of RES, a considerable amount of the generated energy is wasted. The solution is energy storage, which makes it possible to improve the management of power systems. The objective of this article is to present the concept of electricity storage in the form of the chemical energy of hydrogen (Power to Gas) in order to improve the functioning of the power system in Poland. The expected growth in the installed capacity of wind power plants will result in more periods in which excess energy will be produced. In order to avoid wasting large amounts of energy, the introduction of storage systems is necessary. An analysis of the development of wind power plants demonstrates that the Power to Gas concept can be developed in Poland, as indicated by the estimated installed capacity and the potential amount of energy to be generated. In view of the above, the excess electricity will be available for storage in the form of chemical energy of hydrogen, which
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Abstract

This paper points out assumptions and reasons for using digital technologies, the importance of using digital technologies in teaching and management. It also refers to the digital technologies and digital competences as an essential part of the competency model of a teaching staff in education. It also points out the fact that existing competency models need to be further explored, decomposed, and formulated as an illustration by the digital competences extensions.
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Abstract

In order to improve the efficiency and ensure the security of power supply used in a mine, this paper mainly studies the quasi-resonant flyback secondary power supply and analyzes its operational principles based on the requirements of soft-switching technology. In accordance with the maximum energy of a short-circuit and the request of maximum output voltage ripple, this paper calculates the spectrum value of the output filter capacitor and provides its design and procedures to determine the parameters of the main circuit of power supply. The correctness and availability of this theory are eventually validated by experiments.
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Abstract

In education, information and Communications Technologies mostly play the role of a medium of communication, as well as a means of imparting knowledge. ICT, however, is used less as a subject for student activity, i.e. a subject for students to learn, where they can operate the technology, as in robotics or mechantronics. Information technologies are also very rarely implemented in education as a way for students to build their identity and shape their attitudes towards their outside and inside worlds. In spite of this, in the history of educational technology there have been a number of researchers and educators who have promoted interesting ideas for implementing technologies as tools for human cognitive, affective, psychomotor and moral empowerment. Today such people are also present in education, however, they play unimportant roles on the periphery of formal education. This paper is a reminder of a number of ideas by theorists and researchers concerning the implementation of ICT, but mainly highlights the empowerment it gives students and its humanizing/humanitarian role.
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Abstract

Industry 4.0 and the associated idea of society 4.0 pose specific challenges for the concept of sustainable development. These challenges relate, inter alia, to responsibility, in which the changes to date have overall entailed: • a transition from ex post responsibility to ex ante responsibility (H. Jonas); • a transition from individual responsibility to corporate social responsibility. In the context of society 4.0 there is a need for shared responsibility. The problem of justice and therefore the implementation of sustainable development not only becomes an open problem, but also requires constant updating and specifi c optimisation.
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Abstract

The aim of this paper is to discuss energy certification systems and multi-criteria certification schemes – both the assessment tools focusing on the level of the single building and on the urban level. The role of certification systems and the emerging technologies as a means of reducing energy consumption and achieving the high energy quality of the built environment is investigated.
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Abstract

Recent works of the authors, concerning the future of urban regions, are synthesised in the paper. Three methodological paths – focused on exploring and creating the future of urban regions – are the backbone of the presented work. Within the fi rst path, creation of regional future by applying the concept of intellectual and strategic challenges is recommended. Second path introduces a new perspective for the future, based upon vehicles. A new philosophy of urban and regional growth emerges here. Third path is a new approach towards creation of regional specialisations in a contemporary notion of technological and creative economy.
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Abstract

The environment is the greatest good for the people. Everyone wants to breath air of the best possible quality, whether living in the city center of a metropolis or in a rural area. Air polluted with very fine particles contribute to the negative effect on people’s health and the whole environment. A significant part of air dust pollution comes from the so-called low emissions sources which include: non-standard furnaces, fireplaces, low-efficiency outdated boilers and local heat sources. Since the beginning of Polish Mining Group’s existence, the company actively participates and supports many activities, the aim of which is to improve the air quality by producing and supplying high quality coal for the residential sector. The company has undertaken pro-ecological activities towards creating a new, pro-ecological strategy as well as product offer. The production of an ecological coal assortment is systematically developing but new coal products are also being launched on the market. One of the company’s priorities is the production of thermal coal for the residential sector. Many organizational and technological changes have been made In that area (e.g. the establishmsnt of the Eco-Fuels Production Plant) to ensure a suitable level of production of the highest quality thermal coal.
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Abstract

Among the numerous modern, high-efficiency energy technologies allowing for the conversion of chemical energy of coal into electricity and heat, the Direct Carbon Fuel Cells (DCFC) deserve special attention. These are devices that allow, as the only one among all types of fuel cells, to directly convert the chemical energy contained in solid fuel (coal) into electricity. In addition, they are characterized by high efficiency and low emission of pollutants. The paper reviews and discusses previous research and development works, both around the world and in Poland, into the technology of direct carbon fuel cells with an alkaline (hydroxide) electrolyte.
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Abstract

Thaddeus Bulgarin (1789–1859) – a writer, critic and publishеr. During his activity hеtried to find his place in the history of both Polish and Russian literature and culture. However, neither Poles nor Russian considered him as their national author, despite the fact he was a very popular figure in the first half of the 19th century. Although Bulgarin’s heritage consists of numerous writings in the field of science-fiction literature, his name cannot be аlsо found among its creators. This article analyses the most significant visions of future by Bulgarin, in particular regarding the development of technology and its impact on human beings. Then it could be said that it was not Julius Verne, but Thaddeus Bulgarin, was the first one toprovide readers with travels to the centre of the Earth.
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Abstract

The paper presents the results of investigation into the technological possibility of making light-section castings of GX2CrNiMoN25-6-3 cast steel. For making castings with a wall thickness in the thinnest place as small as below 1 mm, the centrifugal casting technology was employed. The technology under consideration enables items with high surface quality to be obtained, while providing a reduced consumption of the charge materials and, as a result, a reduction in the costs of unit casting production.
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Abstract

The results of testing of the selected group of wax mixtures used in the investment casting technology, are presented in the paper. The measurements of the kinetics of the mixtures shrinkage and changes of viscous-plastic properties as a temperature function were performed. The temperature influence on bending strength of wax mixtures was determined.
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Abstract

There are two methods to produce primary copper: hydrometallurgical and pyrometallurgical. Copper concentrates, from which copper matte is melted, constitute the charge at melting primary copper in the pyrometallurgical process. This process consists of a few stages, of which the basic ones are roasting and smelting. Smelting process may be bath and flash. Slag from copper production, on the end of process contain less 0,8%. It is treat as a waste or used other field, but only in a few friction. The slag amount for waste management or storage equaled 11 741 – 16 011 million tons in 2011. This is a serious ecological problem. The following slags were investigated: slag originated from the primary copper production process in the flash furnace of the Outtokumpuja Company in HM Głogów 2 (Sample S2): the same slag after the copper removal performed according the up to now technology (Sample S1): slag originated from the primary copper production process in the flash furnace of the Outtokumpuja Company in HM Głogów 2, after the copper removal performed according the new technology (Sample S3). In practice, all tested slags satisfy the allowance criteria of storing on the dumping grounds of wastes other than hazardous and neutral.
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Abstract

The work presents experiment results from the area of copper casting technology and chosen examples of alloyed copper. At present, copper casting technology is applied in many branches of industrial manufacturing, especially in the sector of construction, communications, arms and power engineering. Alloyed copper, containing slight additions of different elements and having special physio-chemical properties, is used in a special range of applications. Copper technology and alloyed copper analyses have been presented, these materials being used for cast manufacturing for power engineering. The quality of casts has been assessed, based on their microstructure analysis, chemical content and the cast properties. During the research, special deoxidizing and modifying agents were applied for copper and chosen examples of alloyed copper; also exemplary samples were tested with the help of metallographic analysis, electrical conductivity and gaseous impurities research.
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Abstract

Paper presents the results of evaluation of heat resistance and specific heat capacity of MAR-M-200, MAR-M-247 and Rene 80 nickel superalloys. Heat resistance was evaluated using cyclic method. Every cycle included heating in 1100°C for 23 hours and cooling for 1 hour in air. Microstructure of the scale was observed using electron microscope. Specific heat capacity was measured using DSC calorimeter. It was found that under conditions of cyclically changing temperature alloy MAR-M-247 exhibits highest heat resistance. Formed oxide scale is heterophasic mixture of alloying elements, under which an internal oxidation zone was present. MAR-M-200 alloy has higher specific heat capacity compared to MAR-M-247. For tested alloys in the temperature range from 550°C to 800°C precipitation processes (γ′, γ′′) are probably occurring, resulting in a sudden increase in the observed heat capacity.
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Abstract

The paper presents a method for wireless measurement of car wheel air pressure and temperature using the Tire Pressure Monitoring System, or TPMS module - one of the latest safety systems introduced by the automotive industry - with readings taken on a specifically designed test bench. The paper describes the structure and operating principle of the test bench key elements and how they work with the sensors, the TPMS module, and reference instruments, as well as the data format and accuracy of data transmission between TPMS and the host computer. The software designed for an embedded system emulating the real on-board computer allows for observing raw sensor readings and the effect of calibration in two points of the characteristics.
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Abstract

The casting workshop was discovered with numerous artifacts, confirming the existence of the manufacturing process of metal ornaments using ceramic molds and investment casting technology in Lower Silesia (Poland) in 7-6 BC. The research has yielded significant technological information about the bronze casting field, especially the alloys that were used and the artifacts that were made from them. Based on the analyses, the model alloys were experimentally reconstructed. Taking advantage of the computer-modeling method, a geometric visualization of the bronze bracelets was performed; subsequently, we simulated pouring liquid metal in the ceramic molds and observed the alloy solidification. These steps made it possible to better understand the casting processes from the perspective of the mold technology as well as the melting and casting of alloys.
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Abstract

The paper present the examination results concerning mechanical properties of castings made of AlSi7MG alloy in correlation both with the most significant squeeze casting parameters and with the modification treatment. Experiments were planned and held according to the 2 3 factorial design. The regression equations describing the influence of the squeeze pressure, the mould temperature, and the quantity of strontium modifier on the strength and elongation of the examined alloy were obtained. It was found that the main factor controlling the strength increase is the squeeze pressure, while the plasticity (A5 ) of the alloy is affected most advantageously by modification. The application of modification treatment in squeeze casting technology enables for production of the slab-type castings made of AlSi7Mg alloy exhibiting strength at the level of 230 MPa and elongation exceeding 14%.
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Abstract

The article presents an example of analysis of the influence of selected parameters deriving from data acquisition in foundries on the occurrence of Gas porosity defects (detected by Visual testing) in castings of ductile cast iron. The possibilities as well as related effectiveness of prediction of this kind of defects were assessed. The need to rationally limit the number of possible parameters affecting this kind of porosity was indicated. Authors also benefited from expert group's expertise in evaluating possible causes associated with the creation of the aforementioned defect. A ranking of these parameters was created and their impact on the occurrence of the defect was determined. The classic statistical tools were used. The possibility of unexpected links between parameters in case of uncritical use of these typical statistical tools was indicated. It was emphasized also that the acquisition realized in production conditions must be subject to a specific procedure ordering chronology and frequency of data measurements as well improving the casting quality control. Failure to meet these conditions will significantly affect the difficulties in implementing and correcting analysis results, from which INput/OUTput data is expected to be the basis for modelling for quality control.
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Abstract

Mathematical programming, constraint programming and computational intelligence techniques, presented in the literature in the field of operations research and production management, are generally inadequate for planning real-life production process. These methods are in fact dedicated to solving the standard problems such as shop floor scheduling or lot-sizing, or their simple combinations such as scheduling with batching. Whereas many real-world production planning problems require the simultaneous solution of several problems (in addition to task scheduling and lot-sizing, the problems such as cutting, workforce scheduling, packing and transport issues), including the problems that are difficult to structure. The article presents examples and classification of production planning and scheduling systems in the foundry industry described in the literature, and also outlines the possible development directions of models and algorithms used in such systems.
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Abstract

The problem considered in the paper is motivated by production planning in a foundry equipped with the furnace and casting line, which provides a variety of castings in various grades of cast iron/steel for a large number of customers. The quantity of molten metal does not exceed the capacity of the furnace, the load is a particular type of metal from which the products are made in the automatic casting lines. The goal is to create the order of the melted metal loads to prevent delays in delivery of goods to customers. This problem is generally considered as a lot-sizing and scheduling problem. The paper describes two computational intelligence algorithms for simultaneous grouping and scheduling tasks and presents the results achieved by these algorithms for example test problems.
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Abstract

The problem considered in the paper is motivated by production planning in a foundry equipped with the furnace and casting line, which provides a variety of castings in various grades of cast iron/steel for a large number of customers. The quantity of molten metal does not exceed the capacity of the furnace, the load is a particular type of metal from which the products are made. The goal is to create the order of the melted metal loads to prevent delays in delivery of goods to customers. This problem is generally considered as a lot-sizing and scheduling problem. The paper describes a mathematical programming model that formally defines the optimization problem and its relaxed version that is based on the conception of rolling-horizon planning
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