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Wyświetlanie 1-14 z 14
Tytuł:
Multiplex RT-PCR Reaction for Simultaneous Detection of Tomato Torrado Virus and Pepino Mosaic Virus Co-Infecting Solanum Lycopersicum
Autorzy:
Wieczorek, P.
Obrepalska-Steplowska, A.
Powiązania:
https://bibliotekanauki.pl/articles/65659.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
The tomato (Solanum lycopersicum L.) is cultivated all over the world and is a vegetable of significant economic importance. However, an increased production of the vegetable is directly connected with an elevated occurrence of pathogens limiting the production efficiency of the vegetable. Both, Tomato torrado virus and Pepino mosaic virus have been found to be serious disease factors. When not controlled, these viruses can significantly decrease tomato cultivation. In this article, we report a multiplex reverse transcription-polymerase chain reaction (RT-PCR) protocol for simultaneous detection of both, Tomato torrado virus (ToTV) and Pepino mosaic virus (PepMV) in virus infected plants. The assay was designed to specifically amplify the conserved regions of genomic ribonucleic acid (RNA) of both viruses. Moreover, the glycerandehyde 3-phosphate dehydrogenase (GAPDH) was used as an internal control of amplification to exclude false-negative assay results. High-resolution melt analysis of generated RT-PCR products was additionally performed to increase sensitivity and double-check the specificity of the reaction without the need of subsequent complementary deoxyribonucleic acid (cDNA) sequencing.
Źródło:
Journal of Plant Protection Research; 2013, 53, 3
1427-4345
Pojawia się w:
Journal of Plant Protection Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evolution of the structure and mechanical strength of a coal particle during combustion in the atmosphere of air and the mixture of oxygen and carbon dioxide
Ewolucja struktury oraz wytrzymałości mechanicznej ziarna węgla podczas spalania w atmosferze powietrza oraz mieszaninie tlenu i dwutlenku węgla
Autorzy:
Pełka, P.
Golański, G.
Wieczorek, P.
Powiązania:
https://bibliotekanauki.pl/articles/219361.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
spalanie
rozdrabnianie
właściwości mechaniczne
combustion
comminution
mechanical properties
Opis:
The research was conducted on the basis of four different types of hard coal and one type of brown coal. There are typical coals commonly used as fuel in Polish CFB boilers. The combustion process was conducted at a temperature of 850°C and the atmosphere of ambient air as well as in the mixture of oxygen and carbon dioxide in different proportions. The research was carried out using specially prepared cubical coal particles with measurements of 15×15mm and also 10×10 mm. The change of the mechanical properties was analyzed based on three parameters, i.e. compression strength, Vickers hardness and fracture toughness. The analysis was supplemented by microscopic images of the surface of the particles using an atomic force microscope. The results obtained clearly indicated the mechanical changes of the coal during its combustion, particularly at the moment of ignition of the char. Moreover, the results correlate very well with the processes of coal comminution that have been described by other authors (Basu, 1999; Chirone et al., 1991) during combustion in the circulating fluidized bed and also explain the sudden change of susceptibility to erosion in the conditions with and without combustion. The measured values can be used as strength parameters in the modelling of the mass loss of coal particles in conditions of circulating fluidized bed combustor that are hard to describe.
Badania przeprowadzono na podstawie czterech węgli kamiennych różnego typu oraz jednego węgla brunatnego. Są to typowe węgle energetyczne wykorzystywane powszechnie jako paliwo w kotłach fluidyzacyjnych w Polsce. Proces spalania był prowadzony w temperaturze 850°C w atmosferze powietrza atmosferycznego oraz w atmosferze mieszaniny tlenu oraz dwutlenku węgla w różnych proporcjach. Badania przeprowadzono na spreparowanych do tego celu sześciennych próbkach węgla o wymiarach 15×15 mm oraz 10×10 mm. Zmianę własności mechanicznych przeanalizowano w oparciu o trzy parametry: wytrzymałość na ściskanie, twardości Vickersa oraz współczynnik kruchości. Analizę uzupełniono zdjęciami mikroskopowymi powierzchni ziaren wykonanymi za pomocą mikroskopu sił atomowych. Otrzymane rezultaty wskazują na bardzo wyraźne zmiany wytrzymałościowe węgla podczas jego spalania, szczególnie w chwili zapłonu karbonizatu. Uzyskane wyniki bardzo dobrze korelują z opisywanymi przez innych autorów procesami rozdrabniania węgla (Basu, 1999; Chirone et al., 1991) podczas spalania w warunkach cyrkulacyjnej warstwy fluidalnej. Tłumaczą gwałtowną zmianę podatności na erozję w warunkach bez spalania oraz z towarzyszącym spalaniem. Rezultaty badań mogą posłużyć jako parametry wytrzymałościowe w modelowaniu ubytku masy ziaren węgla w trudnych do opisania warunkach cyrkulacyjnej warstwy fluidalnej.
Źródło:
Archives of Mining Sciences; 2013, 58, 3; 673-690
0860-7001
Pojawia się w:
Archives of Mining Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessment Of Joints Using Friction Stir Welding And Refill Friction Stir Spot Welding Methods
Diagnostyka połączeń uzyskanych metodą tarciową (Friction Stir Welding) oraz zgrzewania z przemieszaniem materiału (Refill Friction Stir Spot)
Autorzy:
Lacki, P.
Więckowski, W.
Wieczorek, P.
Powiązania:
https://bibliotekanauki.pl/articles/352059.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
friction stir welding
investigation
defects
FSW
diagnostyka złączy
defekty
Opis:
FSW (Friction Stir Welding) and RFSSW (Refill Friction Stir Spot Welding) joints have been increasingly used in industrial practice. They successfully replace fusion-welded, riveted or resistance-welded joints. In the last two decades, dynamic development of this method has stimulated investigations of the fast methods for joint diagnostics. These methods should be non-destructive and easy to be used in technological processes. The methods of assessment of joint quality are expected to detect discontinuities in the structures welded using FSW and FSSW methods. Reliable detection of flaws would substantially extend the range of applications of FSW joints across many sectors of industry, including aviation. The investigations carried out in this paper allowed for characterization of defects present in FSW and RFSSW joints. Causes of these defects were also stressed. An overview of the methodologies for assessment of joint quality was presented. Results of assessment of the quality of joints made of 2024T6 aluminium sheet metal using FSW and RFSSW method were presented.
Złącza FSW i RFSSW są coraz częściej stosowane w praktyce przemysłowej. Dobrze zastępują złącza spawane, nitowane czy zgrzewane oporowo. Dynamiczny rozwój metod w ostatnim dwudziestoleciu skutkuje poszukiwaniem szybkich metod diagnostyki złączy. Metody te powinny być nieniszczące oraz dać się zastosować podczas procesu technologicznego. Od sposobu oceny jakości złączy oczekuje się wykrycia nieciągłości struktur zgrzewanych metodą FSW i FSSW. Możliwość skutecznego wykrywania wad pozwoliłaby na znacznie szerszy zakres zastosowań złączy FSW w wielu sektorach przemysłu w tym w przemyśle lotniczym. Na podstawie przeprowadzonych badań w pracy przedstawiono charakterystykę defektów występujących w złączach FSW i RFSSW, wskazano na przyczyny ich występowania oraz przedstawiono przegląd metod badań umożliwiających ocenę jakości złączy. Zaprezentowano przykładowe wyniki oceny jakości złączy wykonanych z blach aluminiowych 2024T6 metodą FSW i RFSSW.
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 3; 2297-2306
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Examinations of the Welded Joint T91 Steel After Service at Elevated Temperature
Autorzy:
Golański, G.
Merda, A.
Klimaszewska, K.
Wieczorek, P.
Powiązania:
https://bibliotekanauki.pl/articles/352311.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
T91 steel
welded joint
microstructure
hardness
microhardness
Opis:
The article provides results of the microstructure examinations and mechanical properties (hardness and microhardness tests) of the welded joint T91 steel taken from the live steam pipeline. Examined joint has been exploited for about 45 000 hours in a temperature of 535°C and the steam pressure equals to 13.5 MPa. Examined joint was made as a double bead by the additional materials with a different chemical composition. It was proved that the joint was characterized by a differential microstructure on the cross-section of the weld. Moreover, decarburized zone in the lower alloyed material and carbides zone in the higher alloyed material were revealed in the weld line and on the boundary penetration of beads. Furthermore, it was shown that the main mechanism of a joint degradation is a privileged precipitation of carbides on the grain boundaries, and an increase of their size.
Źródło:
Archives of Metallurgy and Materials; 2020, 65, 1; 237-242
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Segregation of Elements in Continuous Cast Carbon Steel Billets Designated for Long Products
Autorzy:
Hutny, A. M.
Warzecha, M.
Derda, W.
Wieczorek, P.
Powiązania:
https://bibliotekanauki.pl/articles/354222.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
continuous casting
billet
segregation
Opis:
This article presents research results concerning designation of the scope of segregation of elements by analysing the ingot, designated for hot rolling of long products. The research tests were performed under industrial conditions, during continuous casting production cycle of high carbon steels. From cc ingots with square cross-section of 160 mm samples having the length of 400 mm were collected, out of which two samples were cut up, the so-called templates with the thickness of 20 mm. Segregation of elements was determined based on the quantitative analysis of results performed by using spark spectrometry pursuant to PN-H-04045. Changes in concentrations of elements were analysed along the line, which join the opposite sides of the sample in their half length and pass through the geometric centre of the square cross-section. In the further course of the research study, there was also determined the segregation along perpendicular line up to the surface connecting the core of the cross-section with lateral plane. Designations of element contents were performed at points distanced from each other by approx. 10 mm and situated on the lines. There was found segregation of carbon, sulphur and phosphorus.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 4; 2037-2042
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Segregation of Elements in Billets Made of Carbon Steels for Long Products
Autorzy:
Hutny, A. M.
Warzecha, M.
Wieczorek, P.
Derda, W.
Powiązania:
https://bibliotekanauki.pl/articles/354733.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
steelmaking
continuous casting
billet
segregation
optical emission spectrometry
Opis:
The article presents the results of investigations performed on segregation of elements in the billets. The research were performed under standard industrial conditions, during high carbon steel production cycle. Probes (templates with the thickness of 20 mm) were taken from billets with square cross-section of 160 mm. Segregation of elements was determined based on the quantitative analysis of results performed by using spark spectrometry pursuant to PN-H-04045. Changes in concentrations of elements were analysed along two cross-sections. Element contents were performed at points distanced from each other by approx. 10 mm. The segregation of carbon, sulphur and phosphorus was determined for different billets.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 4; 2075-2079
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Analysis of Filler Material Effect on Properties of Excavator Crawler Track Shoe after Welding Regeneration
Autorzy:
Gucwa, M.
Winczek, J.
Wieczorek, P.
Mičian, M.
Koňár, R.
Powiązania:
https://bibliotekanauki.pl/articles/2049557.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
hardfacing
carbides
hardness
wear
covered electrode
Opis:
The application of hardfacing is one of the ways to restore the functional properties of worn elements. The possibility of using filler materials rich in chrome allows for better wear resistance than base materials used so far. The paper presents the results of research on the use of 3 different grades of covered electrodes for the regeneration of worn track staves. The content of the carbon in the covered electrodes was from 0,5% to 7% and the chromium from 5% to 33%. The microscopic and hardness tests revealed large differences in the structure and properties of the welds. The differences in the hardness of the welds between the materials used were up to 150 HV units. The difference in wear resistance, in the ASTM G65 test, between the best and worst materials was almost 12 times big.
Źródło:
Archives of Metallurgy and Materials; 2021, 66, 1; 31-36
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The domain structure of die-upset anisotropic magnet based on Nd-(Fe, Co)-B alloy
Struktura domenowa anizotropowego odkształconego na gorąco magnesu na bazie związku Nd-(Fe, Co)-B
Autorzy:
Płusa, D.
Dośpial, M.
Derewnicka-Krawczyńska, D.
Wieczorek, P.
Kotlarczyk, U.
Powiązania:
https://bibliotekanauki.pl/articles/354074.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
exchange interactions
high coercivity materials
permanent magnets
domain walls and domain structure
Opis:
The measurements of the recoil curves for the die-upset Nd-(Fe, Co)-B based magnets from different points on the magnetization and demagnetization curves have been carried out by means of the LakeShore vibrating sample magnetometer in an applied magnetic fields up to 2 T. From the recoil curves the so-called Wohlfarth's remanence relationship has been derived. From this it was deduced that the magnetic interaction existing between the magnet grains has a dipolar nature. The existence of the magnetic interaction has been confirmed by magnetic domain observations by using the magnetic force microscopy (MFM). In the area of interaction domains there is the fine scale magnetic contrast resulting from the dipolar interaction between neighboring grains.
Za pomocą magnetometru wibracyjnego firmy LakeShore wyznaczono krzywe powrotne dla spęczanych magnesów Nd-(Fe, Co)-B w polu magnetycznym do 2 T. Na podstawie krzywych powrotnych wyznaczono zależność remeanencyjną Wohlfartha. Z zależności tej wynika, że oddziaływania magnetyczne pomiędzy ziarnami to dalekozasięgowe oddziaływania dipolowe. Obecność tych oddziaływań została potwierdzona przez obserwację struktury domenowej za pomocą mikroskopu sił magnetycznych (MFM). Oscylacyjne zmiany kontrastu, występujące w obszarach zbliżonych do wielkości ziaren, świadczą o istnieniu uporządkowania magnetycznego w tych obszarach, które jest wynikiem oddziaływania dipolowego między sąsiednimi ziarnami.
Źródło:
Archives of Metallurgy and Materials; 2011, 56, 1; 159-161
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quantitative analysis of stability of 9%Cr steel microstructure after long-term ageing
Autorzy:
Golański, G.
Jasak, J.
Zieliński, A.
Kolan, C.
Urzynicok, M.
Wieczorek, P.
Powiązania:
https://bibliotekanauki.pl/articles/353244.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
high-chromium martensitic steels
microstructure
carbide precipitation
Opis:
The paper presents the results of research on the microstructure of martensitic X10CrMoVNb9-1 (P91) and X13CrMoCo- VNbNB9-2-1 (PB2) steel subject to long-term ageing at the temperature of 620°C and holding times up to 30 000 hours. The microstructural tests of the examined steel types were performed using a scanning microscope Joel JSM - 6610LV and a transmission electron microscope TITAN 80 - 300. The stability of the microstructure of the investigated steels was analyzed using a quantitative analysis of an image, including measurements of the following: the density of dislocations inside martensite/subgrain laths, the width of martensite laths, and the mean diameter of precipitates. It has been concluded that during long-term ageing, the microaddition of boron in PB2 steel significantly influenced the slowing of the process of degradation of the martensitic steel microstructure, as a result of slowing the process of coagulation of M23C6 carbides and Laves phase. It had a favorable effect on the stabilization of lath microstructure as a result of retardation of the processes of recovery and polygonization of the matrix.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 1; 263-271
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Examination of the Properties of Samples from Glass-Epoxy Core Rods for Composite Insulators Subjected to DC High Voltage
Autorzy:
Wieczorek, K.
Jaroszewski, M.
Ranachowski, P.
Ranachowski, Z.
Powiązania:
https://bibliotekanauki.pl/articles/351254.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
DC high voltage
composite insulator
glass-epoxy core
dielectric spectroscopy
Raman spectroscopy
Opis:
This article presents the results of an examination performed on a set of samples of glass-epoxy core rods used in composite insulators with silicone rubber housings. The goal of the examination was to test the aging resistance of the core material when exposed to Direct Current (DC) high voltage. Long term exposure of a glass-epoxy core rod to DC high voltage may lead to the gradual degradation of its mechanical properties due to the ion migrations. Electrolysis of the core material (glass fiber) may cause electrical breakdown of the insulators and consequently lead to a major failure. After being aged for 6000 hours under DC high voltage, the samples were subjected to microscopic analysis. Their chemical composition was also examined using Raman spectroscopy and their dielectric losses and conductance in the broad range of frequencies were tested using dielectric spectroscopy.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 3; 1281-1286
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of the Quality of Coatings Deposited on AZ31 Magnesium Alloy Using the Anodising Method
Jakości powłok wykonanych na stopie magnezu Az31 metodą anodowania
Autorzy:
Wieczorek, J.
Oleksiak, B.
Mizera, J.
Kulikowski, K.
Maj, P.
Powiązania:
https://bibliotekanauki.pl/articles/351825.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
magnesium alloys
protective coatings
anodising
scratch test
erosion testing
stopy magnezu
powłoki ochronne
anodowanie
próba zarysowania
badania erozji
Opis:
The paper presents results of a study on the quality of coatings deposited on surfaces of AZ31 magnesium alloy products. In order to obtain protective coatings (corrosion and erosive wear protection), the methods of anodising (specimens A, B and C) and, for comparison, electroless plating (specimen D) were applied. The assessment of coating quality was based on the scratch test results. The results were used for determination of critical loads resulting in coating rupture. The best result was obtained for the specimen B (sulphuric acid anodising in combination with sealing): the critical load was 7.5 N. The smallest value (5.5 N) was observed for the specimen D, i.e. the coating produced using the electroless plating method. Moreover, erosion resistance of the coatings was assessed. In this case, a depth of the wear trace due to an erodent agent (SiC powder) effects was investigated. The results are comparable to those obtained in the scratch test. The poorest erosion resistance is demonstrated by the coating D and the best resistance is observed for the coating B.
W artykule przedstawiono wyniki badań jakości powłok wytworzonych na powierzchni wyrobów ze stopu magnezu AZ31. Dla wytworzenia powłok o charakterze ochronnym (ochrona przed korozją i zużyciem erozyjnym), zastosowano metodę anodowania (próbki A, B i C) oraz dla porównania metodę bezprądową (próbka D). Ocenę jakości powłok oparto o wynik próby zarysowania (scratch-test). Na podstawie uzyskanych wyników wyznaczono krytyczne obciążenie, przy którym następuje przebicie powłoki. Najlepszy wynik uzyskano w przypadku próbki B (anodowanie w kwasie siarkowym połączone z uszczelnianiem), wartość krytycznego obciążenia wynosiła 7.5 N. Najmniejszą wartość obciążenia krytycznego 5.5 N, zarejestrowano w przypadku próbki D tj. powłoki wytworzonej bezprądowo. Oceniono także odporność powłok na zużycie erozyjne. W tym przypadku badano głębokość śladu powstałego wskutek oddziaływania na powierzchnię próbek ścierniwa (proszek SiC). Uzyskane wyniki są podobne do zarejestrowanych w próbie zarysowania. Najmniejszą odpornością na erozję charakteryzuje się powłoka wytworzona bezprądowo (D) a największą powłoka anodowana i uszczelniana (B).
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 4; 2843-2850
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Degradation Processes in Shield-Centring Elements of Surge Arresters
Autorzy:
Papliński, P.
Śmietanka, H.
Ranachowski, P.
Ranachowski, Zbigniew
Wieczorek, K.
Kudela, S. jr.
Powiązania:
https://bibliotekanauki.pl/articles/2203744.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
surge arrester
TSE glass textolite
discharge current
EDS method
Opis:
This paper presents the results of testing samples of shield-centering elements from medium-voltage surge arresters. The elements were made of TSE glass textolite. The elements have been dismantled from different operated surge arresters, which were subjected to discharge currents (short-circuit currents) of different intensity and duration. The discharge currents led to degradation of the tested elements with various degrees of advancement. The degradation was investigated using microscopic methods and energy-dispersive X-ray spectroscopy (EDS). Changes in the content of elements of the surface of textolite materials - as the degradation progresses - were documented. It was found that high discharge current flows resulted in melting of the organic binder, epoxy resin, especially its surface layer. Partial charring and even burning of the resin was noticeable. Furthermore, it was found that with increasing degradation on the surface of the TSE laminate, the carbon and oxygen content, which are part of the organic resin, decreases. Simultaneously the amount of silicon, calcium and aluminium, which are present in the glass fibres, increases. The charring effect of the resin and the formation of conductive paths result in a decrease in the performance of surge arresters and their subsequent failure.
Źródło:
Archives of Metallurgy and Materials; 2023, 68, 1; 237--242
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of Modified Aluminous Porcelain Subjected to Mechanoacoustic Tests
Autorzy:
Ranachowski, P.
Ranachowski, Z.
Wieczorek, K.
Jaroszewski, M.
Kudela, S. jr.
Powiązania:
https://bibliotekanauki.pl/articles/355059.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
electrical porcelain materials
ageing processes
acoustic emission
AE
optical microscopy
Opis:
The paper presents the microscopic and mechanoacoustic study of degradation processes of the porcelain material C 130 type. This kind of material is used in the production of the most durable and reliable electrotechnical elements. Raw material composition of the studied porcelain was modified. This had an impact on the inner properties, cohesion and – in consequence – on operational properties of the material. Using mechanical-acoustic and microscopic methods of testing of small-size samples that were subjected to compression, it was possible to distinguish successive stages of degradation of the porcelain structure. These stages were generally typical of the porcelain materials. In the authors’ opinion, they are connected to the ageing process happening over many years of work under operating conditions. Optimization of composition and technological properties – important during technological processes – resulted in a slight decrease in inner cohesion of the porcelain. When compared to the reference material – typical domestic C 130 material, mechanical strength was somewhat lower. Carried out investigations proved that resistance of the investigated material to the ageing degradation process – during long term operation – also decreased. The improvement of technological parameters and the reduction in the number of defective elements occurred simultaneously with some decrease in the operational parameters of the material. To restore their initial high level, further work is needed to optimize the raw material composition of the porcelain.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 4; 1821-1826
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Developing automatic recognition system of drill wear in standard laminated chipboard drilling process
Autorzy:
Kurek, J.
Kruk, M.
Osowski, S.
Hoser, P.
Wieczorek, G.
Jegorowa, A.
Górski, J.
Wilkowski, J.
Śmietańska, K.
Kossakowska, J.
Powiązania:
https://bibliotekanauki.pl/articles/200766.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
diagnostic expert systems
neural networks
wavelet packets
wear monitoring
diagnostyczny system ekspercki
sieci neuronowe
pakiety falkowe
monitorowanie zużycia
Opis:
The paper presents an automatic approach to recognition of the drill condition in a standard laminated chipboard drilling process. The state of the drill is classified into two classes: “useful” (sharp enough) and “useless” (worn out). The case “useless” indicates symptoms of excessive drill wear, unsatisfactory from the point of view of furniture processing quality. On the other hand the “useful” state identifies tools which are still able to drill holes acceptable due to the required processing quality. The main problem in this task is to choose an appropriate set of diagnostic features (variables), based on which the recognition of drill state (“useful” versus “useless”) can be made. The features have been generated based on 5 registered signals: feed force, cutting torque, noise, vibration and acoustic emission. Different statistical parameters describing these signals and also their Fourier and wavelet representations have been used for defining the features. Sequential feature selection is applied to detect the most class discriminative set of features. The final step of recognition is done by using three types of classifiers, including support vector machine, ensemble of decision trees and random forest. Six standard drills of 12 mm diameter with tungsten carbide tips were used in experiments. The results have confirmed good quality of the proposed diagnostic system.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2016, 64, 3; 633-640
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
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