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EN
Purpose: The aim of this paper is to present a modern manufacturing method of production and compare the thermal, mechanical, properties of composite materials with aluminium alloy matrix reinforced by Al2O3 particles. Design/methodology/approach: The material for investigation was manufactured by the method of powder metallurgy (consolidation, pressing, hot concurrent extrusion of powder mixtures of aluminium EN AW-AlCu4Mg1 (A) and ceramic particles Al2O3). The amount of the added powder was in the range of 5 mass.%, 10 mass.% and 15 mass.%. Findings: The received results concerning the enhancement of hardness, which show the possibility of obtaining the MMC composite materials with required microstructure, influencing the properties of the new elaborated composite materials components. Concerning the thermal properties, especially the linear thermal expansion coefficient was measured, as well as the dilatometric change of the sample length was analysed. Practical implications: Concerning practical implications it can be stated that the tested composite materials can be applied among others in the transportation industry, but it requires additional research. Originality/value: The received results show the possibility of obtaining new composite materials with controlled and required microstructure with possible practical implications.
EN
The article presents the possibility of applying artificial intelligence to forecast necessary repairs on ordinary railway switches. Railway switch data from Katowice and Katowice Szopienice Północne Stations were used to model neural structures. Using the prepared data set (changes in values of nominal dimensions in characteristic sections of 15 railway switches), we created three variants of railway switch classifications. Then, with the results, we determined the values of classifiers and the low mean absolute error, as well as compared charts of effectivity. It was calculated that the best solution by which to evaluate necessary repairs in railway switches was, in part, to repair the crossing nose. It was assessed that a structure with single output data was more effective for the accepted data.
PL
Celem artykułu jest ukazanie istoty kształcenia, zgodnie z rozwojem mózgu ucznia. Szkoła w obecnym kształcie nie wykorzystuje w pełni potencjału uczniów. Współczesny świat jest bardzo zmienny, człowiek musi się ciągle dostosowywać do nowej rzeczywistości, jednak system nauczania jest taki sam jak kilkanaście lat temu. Spojrzenie na proces edukacji z perspektywy neurodydaktyki pozwala zrozumieć mechanizmy zachodzące w mózgach uczniów, a także wskazać jak stosowanie określonych metod nauczania wpływa na jego aktywizację. Celem artykułu jest ukazanie nowych możliwości, jakie niosą interdyscyplinarne badania z zakresu neurobiologii i edukacji, podkreślenie zależności pomiędzy jakością polskiego szkolnictwa a funkcjonowaniem uczniów w środowisku społecznym i ekonomicznym.
EN
The objective of this article is to present the essence of education, in accordance with the development of the student’s brain. School, as it is now, does not fully put to use the students’ potential. The modern world is very changeable, people need to adjust to a new reality on a regular basis, however, the system of education has not changed for several years. Looking at the educational process from the point of view of neurodidactics allows us to understand the underlying mechanisms occurring in the brains of the students, and it can show how using particular teaching methods activate the brain. The objective of the article is to present new possibilities of interdisciplinary research in the field of neurobiology and education, emphasizing the relationship between the quality of Polish education and the functioning of students in the social and economic environment.
EN
In this work, we presented the influence of the anodizing method and parameters, as well as the chemical composition of the used aluminium alloys on the properties and microstructure of the anodic layer produced on aluminium alloys, in particular on the size and morphology of the primary silicon precipitates and the homogeneity of the resulting oxide coating. Aluminium alloys AlSi8 and AlSi12, produced using the die-casting method and subsequently subjected to anodic oxidation were used as test material. The microstructure of the obtained surface layer was analyzed by taking into account the primary silicon precipitates. The results of the hardness and abrasive wear test also show the influence of anodizing and electrolyte parameters on the structure and properties of the tested aluminium alloys.
5
Content available remote Kupować czy modernizować tabor kolejowy?
PL
W artykule analizie poddano dwie opcje odnowy taboru kolejowego - modernizacje starych jednostek lub zakup nowych wagonów. Autor przywołuje przykłady realizowanych inwestycji na terenie kraju i porównuje koszty obu rozwiązań. Przywoływane są także rozwiązania prawne, odmienne od tych obowiązujących w krajach ościennych. Natomiast w celu uzyskania jednoznacznej odpowiedzi na pytanie zawarte w tytule zastosowano analizę wielokryterialną.
EN
The paper analyses two options of rolling stock improvement - modernization of old units or purchase of new cars. The author refers to examples of investments carried out in the country and compares costs of both solutions. Also legal solutions are referred to, different from those in force in neighbouring countries. However, to obtain a clear answer to the question included in the title a multi-criterion analysis was applied.
PL
W artykule scharakteryzowano zasady budowy obwodów bardzo niskiego napięcia (ELV) oraz obszar ich zastosowań. Przedstawiono metody badań skuteczności ochrony przeciwporażeniowej. Zwrócono uwagę na możliwe stany pracy tego typu obwodów, mogące skutkować zagrożeniem pożarowym.
EN
The principles of the construction of ­extra low voltage (ELV) circuits and the area of their applications have been characterized. Methods of testing the effectiveness of protection against electrical shock were presented. Attention has been paid to the possible states of operation of such circuits that could result in fire hazards.
PL
W artykule przedstawiono zagadnienia związane z zagrożeniem porażeniowym i pożarowym występującym w obwodach związanych z energetyką ze źródeł odnawialnych. Przeanalizowano różne możliwe układy pracy instalacji przy takim zasilaniu. Przedstawiono możliwe problemy przy eksploatacji takich układów.
EN
The article presents issues related to the risk of paralysis and fire occurring in the circuits associated with the energy from renewable sources. Various possible operating states of the installation with such a power supply were analyzed. Possible problems in the operation of such systems were presented.
EN
Archaeometallurgical investigations presented in this work focus on analysing the microstructure as well as mechanical properties of artefacts from the17th in form of findings performed from cast iron as well as copper casts. The presented research results extend the up-to-date knowledge and present the analysis of structural compounds found in the microstructure of the artefacts from the time dating back to the late Middle Ages in the region around Czestochowa, Poland. The tested samples were found in earth in the city centre under the present marketplace. The excavation works were carried out in summer in the year 2009, and have resulted in the excavation of artefacts in form of copper block of the weight of several kg. The excavation action was led by a group of Polish archaeologists collaborating with the local authorities. The performed pre-dating of this element determines the age of the artefacts as the 17th century AD. The excavations that have been taking place since 2007 have widened the knowledge of the former Czestochowa. Historians of this town have suggested, that the found weight and traces of metallurgical activity suggest that the exposed walls were an urban weight. The weight is visible on the 18th century iconography. What was find on the Old Market indicates that there was a lush economic life before the Swedish invasion in this part of Poland. Some buildings lost their functions or were changed, others died in fires, but new places developed. To describe the microstructure, with its structural components, research was done using microscopy techniques, both of the light as well as electron microscopy (SEM), also chemical composition analysis was carried out using the EDS technique, as well as tool for phase analysis were applied in form of X-Ray Diffraction (qualitative analysis), especially for the reason to describe the phases present in the excavated material. This research will help to obtain new information in order to investigate further archaeometallurgical artefacts, extending the knowledge about middle age metallic materials its usage and manufacturing.
PL
Kompozyty WPC są materiałami łączącymi zalety tworzyw polimerowych z estetycznym wyglądem naturalnego drewna. Dzięki wprowadzeniu znacznych ilości napełniacza organicznego produkty z nich wykonane mogą być obrabiane za pomocą typowych narzędzi stolarskich, co stanowi znaczne ułatwienie dla użytkowników. Jednocześnie dzięki osnowie polimerowej możliwe jest ich wytwarzanie typowymi metodami stosowanymi w przetwórstwie materiałów termoplastycznych, czyli wytłaczania i wtryskiwania, co wpływa na redukcję kosztu produkcji. W artykule przedstawiono charakterystykę tej grupy materiałów, sposoby ich wytwarzania oraz przetwarzania do postaci gotowego produktu. Zaprezentowano również przykłady wykorzystania kompozytów WPC w różnych gałęziach przemysłu, w szczególności motoryzacji. Ważną część publikacji stanowi analiza wpływu napełniacza organicznego, w szczególności jego postaci geometrycznej i ilości na właściwości fizykomechaniczne finalnego wyrobu.
EN
WPC composites are materials that combine the advantages of plastic with the aesthetic appearance of natural wood. Thanks to the large amount of organic filler, WPC composite products can be machined using ordinary carpenter tools, which make them very easy to work with. At the same time, thanks to the polymer matrix, it is possible to manufacture them by normal methods used in the processing of thermoplastics, in example extrusion and injection molding, which results in lower production costs. The article presents characteristics of this group of materials, methods of their production and processing into finished product. There are also examples of the use of WPC composites in various fields of industry, especially automotive. An important part of the publication is an analysis of the effect of the organic filler, in particular its geometrical form and quantity, on the physicomechanical properties of the final product.
10
Content available Automated transfer point URB/ZS-3
EN
In the KGHM Polska Miedź S.A. mines, excavated material is transported by transport trucks to transfer points and then by belt conveyors to near-shaft storage reservoirs, from where the excavated material is transported to the surface by means of a shaft transport system. Transfer from the means of non-continuous haulage to the continuous transport systems takes place at transfer points, where the excavated material is divided into two fractions: oversized grain and undersized grain. The oversized excavated material (which stays on the grating) is subjected to a process of crushing with the use of jack hammers. The article describes the URB/ZS-3 device for the automatic cleaning of the grating at transfer points, and briefly describes the design and principle of operation of the device. It also presents the purpose of constructing a block-crushing device and the method of its automation.
PL
W kopalniach KGHM Polska Miedź S.A. urobek transportowany jest za pomocą wozów transportowych do punktów przesypowych, a następnie przenośnikami taśmowymi do przyszybowych zbiorników retencyjnych, skąd jest wydobywany na powierzchnię transportem szybowym. Przeładunek ze środków odstawy nieciągłej na ciągłe systemy transportowe odbywa się w punktach przesypowych, gdzie urobek dzielony jest na dwie frakcje, nadziarno i podziarno. Nadgabarytowy, pozostający na kracie, urobek poddawany jest procesowi kruszenia z użyciem młotów udarowych. W artykule opisano urządzenie URB/ZS-3 do automatycznego oczyszczania kraty na punkcie przesypowym, skrótowo opisano konstrukcję i zasadę działania. Przedstawiono cel budowy i sposób automatyzacji urządzenia do rozbijania brył.
PL
W artykule przedstawiono koncepcję struktury układu sterowania obudową podporową do niskich ścian. W pierwszej części artykułu przedstawiono konstrukcję obudowy i jej właściwości, sposób jej działania i współdziałania z pozostałymi elementami kombajnowego kompleksu ścianowego. Na podstawie analizy pracy obudowy i kompleksu ścianowego formułowano założenia, ograniczenia oraz wymagania dotyczące układu sterowania obudową. W dalszej części artykułu opisano strukturę układu pomiarowego i sterującego oraz omówiono poszczególne bloki funkcjonalne układu. Prace badawcze w tym zakresie zostały zrealizowane w ramach projektu pt. Prace studialne i badawcze nad opracowaniem zmechanizowanej obudowy nowego typu do pokładów cienkich, dofinansowanego z Narodowego Centrum Badań i Rozwoju (NCBiR).
EN
The paper presents a conception of a structure of control system dedicated for new roof support of low longwall systems. In the first part of the paper the new construction of roof support is presented. Its properties, method of operation and interaction with other elements of longwall system is described too. Next, based on the analysis of the work manner of the support and whole longwall system assumptions, limitations and requirements on the control circuit are formulated. At the end of this paper the structure of the measuring and control system is decribed and its functional blocks are discussed. Research in this field were conducted under the project entitled Studies of development of innovation hydraulic roof support for low seams. The project is funded by the National Center of Research and Development (NCBiR).
EN
In Poland, researchers have a very strong interest in archaeometallurgy, which, as presented in classical works, focuses on dating artefacts from the prehistoric and early medieval periods in the form of cast iron and copper castings. This study, extending the current knowledge, presents the results of a microstructure investigation into the findings from the Modern era dating back to the late Middle Ages. The investigated material was an object in the form of a heavy solid copper block weighing several kilograms that was excavated by a team of Polish archaeologists working under the direction of Ms Iwona Młodkowska-Przepiórowska during works on the marketplace in the city of Czestochowa during the summer of 2009. Pre-dating of the material indicates the period of the seventeenth century AD. The solid copper block was delivered in the form of a part shaped like a bell, named later in this work as a “kettlebell”. To determine the microstructure, the structural components, chemical composition, and homogeneity, as well as additives and impurities, investigations were carried out using light microscopy, scanning electron microscopy including analysis of the chemical composition performed in micro-areas, and qualitative X-ray phase analysis in order to investigate the phase composition. Interpretation of the analytical results of the material’s microstructure will also help modify and/or develop new methodological assumptions to investigate further archaeometallurgical exhibits, throwing new light on and expanding the area of knowledge of the use and processing of seventeenth-century metallic materials.
PL
W artykule przedstawiono porównanie materiałów polimerowych oraz ceramicznych używanych w stomatologii oraz metody ich badań, jak również zostały opracowane i przedstawione wyniki tych badań. Do analizy struktury materiałów wykorzystano spektroskopie Ramana oraz skaningowy mikroskop elektronowy (SEM) wyposażony w spektrometr dyspersji energii promieniowania rentgenowskiego (EDS).
EN
This article presents analyze the structure of the used poly(methyl methacrylate) PMMA, opaker, dentyna and enamel in stomatology practice. Next part presents properties of this materials. In order to analyze the structure of the used materials were used Raman spectroscopy. To examine the morphology and chemical composition of the resulting of materials was carried out using a scanning electron microscope (SEM) with energy dispersive spectrometer (EDS).
PL
W artykule scharakteryzowano zasady przygotowania stanowiska pracy przy urządzeniach elektroenergetycznych niskiego napięcia, ze zwróceniem szczególnej uwagi na prace wykonywane przy wyłączonym napięciu. Przedstawiono zasady uziemiania urządzeń lub obwodów wyłączonych spod napięcia, zawarte w aktualnych aktach prawnych. Zaprezentowano najważniejsze zasady doboru uziemiaczy oraz określono zakres ­ badań sprzętu przeznaczonego do uziemiania i zwierania.
EN
Safety rules for workplace preparation with the use of low voltage electrical equipment were presented. Particular attention was paid to the work carried under a power-off. The principles of grounding for devices or circuits remain de-energized (without power) presented in the legal acts were given. The main principles for the selection of portable equipment for earthing were presented. The scope of testing of equipment for earthing and short-circuiting was described.
15
Content available remote Automatyczne urządzenie przeładunkowe URB/ZS-3
PL
W referacie przedstawiono cel budowy i sposób automatyzacji urządzenia do rozbijania brył. Przeprowadzono analizę konstrukcji i sformułowano założenia projektowe oraz wymagania dla systemu automatycznego sterowania urządzeniem. Następnie zaproponowano rozwiązanie obejmujące układ wstępnego oczyszczania kraty i układ sterujący wysięgnikiem z hydraulicznym młotem udarowym. Do identyfikacji parametrów urobku przeanalizowano szereg metod wizyjnych oraz laserowych i radarowych. Opracowano i zaimplementowano algorytmy dla poszczególnych modułów automatycznego systemu sterowania młotem udarowym. Wykonano prototypowy system automatycznego sterowania młotem udarowym.
EN
The paper presents the purpose of the construction and method of automation of equipment breaking solids (URB). An analysis of the structure and formulating design assumptions was made for the system of automatic control device. Then it proposed a solution which includes the initial cleaning of the screen and arm control system with a hydraulic hammer. To identifying the parameters of excavated material analyzed a number of methods of video, laser and radar were made. Algorithms for the individual modules of the automatic control system striking hammer were developed and implemented. The prototype of automatic control system of arm with hydraulic hammer was made.
16
EN
This elaboration shows the effect of combined heat treatment and cold working on the structure and utility properties of alloyed copper. As the test material, alloyed copper CuTi4 was employed. The samples were subjected to treatment according to the following schema: 1st variant - supersaturation and ageing, 2nd variant - supersaturation, cold rolling and ageing. The paper presents the results of inicrostructure, hardness, and abrasion resistance. The analysis of the wipe profile geometry was realized using a Zeiss LSM 5 Exciter confocal microscope. Cold working of the supersaturated solid solution affects significantly its hardness but the cold plastic deformation causes deterioration of the wear resistance of the finally aged CuTi4 alloy.
EN
This paper presents the influence of casting method and anodic treatment parameters on thickness and structure of an anodic layer formed on aluminium alloys. As test materials was used the aluminium alloy AlSi9Cu3, which was adopted to the casting process and anodic treatment. In this paper are presented the wear test results and metallographic examination, aswell as hardness of non-anodised and anodised alloys subjected to anodising process.The investigations were performed using light and electron microscopy (AFM) for the microstructure determination. The morphology and size of the layer was also possible to determine. The anodising conditions for surface hardening and itsinfluence on properties was analysed. The structure of the surface laser tray changes in a way, that there is a different thicknessof the produced layer. The aluminium samples were examined in terms of metallography using the optical microscope withdifferent image techniques as well as light microscope. Improving the anodization technology with appliance of differentanodising conditions. Some other investigation should be performed in the future, but the knowledge found in this researchconcerning the proper process parameters for each type of alloy shows an interesting investigation direction. The combinationof metallographic investigation for cast aluminium alloys - including electron microscope investigation - and anodisingparameters makes the investigation very attractive for automobile industry, aviation industry, and others, where aluminium alloys plays an important role.
EN
An huge interest is observed in last years in metal matrix composite, mostly light metal based, which have found their applications in many industry branches, among others in the aircraft industry, automotive-, and armaments ones, as well as in electrical engineering and electronics, where one of the most important issue is related to the corrosion resistance, especially on the surface layer of the used aluminium alloys. This elaboration presents the influence of ceramic phase on the corrosion resistance, quality of the surface layer its thickness and structure of an anodic layer formed on aluminium alloys. As test materials it was applied the aluminium alloys Al-Si-Cu and Al-Cu-Mg, for which heat treatment processes and corrosion tests were carried out. It was presented herein grindability test results and metallographic examination, as well. Hardness of the treated alloys with those ones subjected to corrosion process were compared.
EN
Purpose: The main goal of this paper is to present the investigation results of microstructural evolution and mechanical properties changes in commercial EN AW 6060) aluminium alloy after intensive plastic deformation, obtained by equal channel angular pressing (ECAP) techniques in an annealed state. Design/methodology/approach: Annealing heat treatment was used to remove various types of internal stress in a commercially available alloy in order to increase workability of the material. The evolution of its properties and material behaviour was evaluated after 2,4,6,and 8 passes of the ECAP process. Findings: It was found that the mechanical properties and microstructure during intensive plastic deformation, such as that during the ECAP process, were changed. Plastic deformation refined grains in the aluminium alloy and increased its mechanical properties. Research limitations/implications: The presented study shows results of the investigated material in an annealed state. Practical implications: The applied processing route allows development of materials characterized by high strength and ultrafine grain microstructure compared to un-deformed annealed aluminium alloy. Originality/value: The work presents data about the influence of intensive plastic deformation on the microstructure and mechanical properties of 6060 aluminium alloy after annealing.
20
Content available remote Influence of aging time and temperature on diffusion of alloyed copper
EN
Purpose: The aim of this study is to determine the impact of aging time and temperature on the diffusion process of alloying elements inside alloyed copper CuCr0,7, CuFe2 and CuTi4. Design/methodology/approach: It was assumed the activation energy for diffusion of small interstitial atoms is smaller than for large substitute atoms. To determine the influence of aging time and temperature on diffusion of alloying elements in binary copper-based alloys CuCr0,7, CuFe2 and CuTi4 it has been necessary to develop a suitable mathematical model. It has been shown that with the increase of time t, the diffusion pathway L is increased, but the impact of time is not as large as the effect forced by altering temperature. In general, multiple increase of time is equivalent to increasing the temperature by a few degrees. Findings: The model should be used to estimate the average atom pathway of chromium, iron or titanium in copper matrix, caused by diffusion, and the diffusion path into the grain boundary without adsorption as a function of time and temperature aging Research limitations/implications: The model should be used to calculate the influence of temperature and time of aging on the atoms diffusion pathway of the alloying elements in the selected alloyed copper types. Practical implications: The results allow to calculate the average atom pathway L (with reasonable error level) for which the diffused atoms achieve the amount of free energy required to overcome the energetic barrier, on the basis of a combination of heat treatment parameters. Originality/value: This paper presents the impact of the aging temperature on diffusion in the alloyed copper CuCr0.7, CuFe2 and CuTi4.
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