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Search results for: HIGH SPEED MILLING
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The spindle speed control for high speed milling vibration surveillance
PublicationW pracy przedstawiono zmodyfikowaną metodę nadzorowania drgań za pomocą sterowania optymalno-liniowego prędkością obrotową wrzeciona. Zamieszczono opis dynamiki skrawania, niestacjonarnego modelu obliczeniowego oraz metody nadzorowania drgań. Wykorzystano model modalny wirującego narzędzia, którego parametry wyznaczono zarówno metodami symulacji komputerowych, jak i - za pomocą eksperymentalnej analizy modalnej. Zamieszczono przykład...
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Towards simulations and experiments of high speed milling vibration surveillance by the spindle speed control
PublicationPraca poświęcona jest nowemu podejściu do nadzorowania drgań wirujących narzędzi we współczesnych frezarkach. Przeprowadzono analizę skrawania smukłym frezem kulistym. Jako rezultat sterowania optymlano-liniowego otrzymano program chwilowych zmian prędkości obrotowej pozwalający uzyskać redukację drgań. Metodę zweryfikowano eksperymentalnie.
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Simulation and experiments of high speed milling vibration surveillence with a use of changing spindle speed
PublicationPraca poświęcona jest nowemu podejściu do nadzorowania drgań wirujących narzędzi w nowoczesnych frezarkach. Przeprowadzono analizy dynamiczne skrawania smukłym frezem kulistym. Opisano dynamikę sterowanego układu nistacjonarnego. Jako rezultat sterowania optymalno-liniowego otrzymano program chwilowych zmian prędkości obrotowej pozwalający uzyskać redukację drgań. Metodę zweryfikowano eksperymentalnie na frezarce Alcera Gambin...
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High speed milling vibration surveillance using modal model of the tool
PublicationPraca poświęcona jest nadzorowaniu drgań wirujących narzędzi w nowoczesnych frezarkach. Przedmiotem rozważań jest proces frezowania szybkościowego smukłym frezem kulistym na 5-osiowym centrum obróbkowym Deckel Maho DMU 50eVolution. Frezowanie smukłymi narzędziami jest często stosowane w przypadku nowoczesnych centrów obróbkowych. Uzasadnienie technologiczne wynika z konieczności dokładnego wykonywania złożonych kształtów geometrycznych...
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Mechatronic design for the high speed milling surveillance of the complex and flexible details
PublicationW pracy przedstawiono mechatroniczny system tworzenia mapy optymalnych prędkości obrotowych wrzeciona. W trakcie frezowania szybkościowego przedmiotów podatnych mogą wystąpić drgania samowzbudne typu chatter. Używana zazwyczaj procedura ustawiania wymaganej prędkości obrotowej wrzeciona metodą prób i błędów, w wielu przypadkach nie jest zalecana. Przedstawiona procedura nadzorowania może doprowadzić do uniknięcia ryzyka wystąpienia...
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Surface roughness analysis of hardened steel after high‐speed milling
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High Speed Milling vibration surveillance with optimal spindle speed based on optimal speeds map
PublicationThe paper presents the method of the surveillance of the self-excited chatter vibration. At first, the workpiece modal parameters are estimated based on experimental data which leads to verification of computational model. Then, for selected surface points optimal spindle speeds are calculated. By considering sufficient amount of points it is possible to build a map of optimal spindle speeds. Experimental results show that this...
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Creation of a map of optimal spindle speeds for a purpose of surveillance of high speed milling of flexible details
PublicationDrgania samowzbudne typu chatter często towarzyszą procesom frezowania szybkościowego. Ich skutkiem są nieodwracalne uszkodzenia powierzchni obrabianej. Mogą one również doprowadzić do intensywnego zużycia narzędzi skrawających, a nawet samej obrabiarki. W pracy przedstawiono metodę umożliwiającą tworzenie mapy optymalnych prędkości obrotowych wrzeciona. Stosowanie podczas procesu frezowania optymalnej prędkości obrotowej wrzeciona...
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A Mechatronic System for Building the Map of Optimal Spindle Speeds During High Speed Milling of Flexible Details
PublicationW pracy przedstawiono mechatroniczny system tworzenia mapy optymalnych prędkości obrotowych wrzeciona w celu nadzorowania drgań typu chatter podczas frezowania szybkościowego przedmiotów podatnych. System ten składa się z części pomiarowej oraz części obliczeniowej, w której wykorzystuje się oprogramowanie autorskie i komercyjne. Na bazie uogólnionego warunku Liao-Younga utworzono mapy optymalnych prędkości obrotowych wrzeciona,...
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Vibration surveillance of high speed ball end milling by the spindle speed control
PublicationPrzedstawiono zmodyfikowaną metodę nadzorowania drgań smukłych wirujących narzedzi skrawających za pomocą sterowania optymalno-liniowego prędkością obrotową wrzeciona. Podano opis dynamiki skrawania, niestacjonarnego modelu obliczeniowego oraz zmodyfikowanej metody nadzorowania drgań. Modyfikacja polega na tym, że do symulacji procesu nadzorowania wykorzystano model modalny freza, zaś parametry tego modelu wyznaczono albo numerycznie,...
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Tool Life and Process Dynamics in High Speed Ball End Milling of Hardened Steel
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A novel method for vibration surveillance during high speed ball end milling of flexible details
PublicationPraca dotyczy nadzorowania drgań podczas obróbki zakrzywionych przedmiotów podatnych frezem kulistym, z uwzględnieniem zgodności parametrów modelu modalnego. Przedstawiono analizę dynamiki niestacjonarnego okładu drgającego, z którego wydzielono podukład modalny, strukturalny i łączący. Zastosowano minimalizację poziomu drgań z dopasowaniem prędkości obrotowej wrzeciona do optymalnego kąta przesunięcia fazowego. Eksperymenty doświadczalne...
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A novel method for vibration surveillance during high speed ball end milling of flexible details
PublicationPraca dotyczy nadzorowania drgań układów niestacjonarnych modelowanych metodą elementów skończonych. Obróbka frezem kulistym przedmiotów podatnych jest często stosowana w przypadku nowoczesnych centrów obróbkowych. Drgania względne narzędzie-przedmiot obrabiany mogą doprowadzić do utraty stabilności i powstania drgań samowzbudnych typu chatter. W pracy proponuje się metodę minimalizacji poziomu drgań poprzez dopasowanie prędkości...
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The spindle speed optimal control in modern milling operations.
PublicationPraca dotyczy modeli obrabiarek ze sprzężeniem zwrotnym, w przypadku których istotne znaczenie mają drgania samowzbudne typu chatter. Opis układu drgającego przedstawiono w postaci dynamiki układu sterowanego, przy czym sygnałem sterującym jest chwilowa zmiana prędkości obrotowej wrzeciona. Rozważano frezowanie czołowe smukłym frezem trzpieniowym na pionowym cent rum frezarskim. Przedstawiono rezultaty przykładów symulacji komputerowych....
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Programmed control of the spindle speed in modern milling machines.
PublicationW pracy przedstawiono nowe podejście do nadzorowania drgań wirujących narzędzi we współczesnych frezarkach. Polega ono na sterowaniu programowym w układach niestacjonarnych. Dotyczy to zamkniętych układów obrabiarek, kiedy to istotną rolę odgrywają drgania samowzbudne typu chatter. Sygnałem sterującym jest chwilowa zmiana prędkości obrotowej. Rozważano frezowanie czołowe smukłym frezem trzpieniowym na pionowym centrum frezarskim....
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Vibration surveillance in modern milling machines by the spindle speed control.
PublicationPraca poświęcona jest nadzorowaniu drgań wirujących narzędzi w nowo-czesnych frezarkach. Polega ono na zastosowaniu sterowania programo-wego w układach niestacjonarnych. Dotyczy to zamkniętych układów obra-biarek, kiedy to istotną rolę odgrywają drgania samowzbudne typu chat-ter. Sygnałem sterującym jest chwilowa zmiana prędkości obrotowej. Rozważano frezowanie czołowe smukłym frezem trzpieniowym na pionowym centrum frezarskim....
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The Method of Finding the Optimal Spindle Speed When Milling Flexible Details
PublicationThe paper presents a new method of vibration reduction during milling of flexible details. The method consists in selecting the optimal spindle speed, based on the natural frequency of the workpiece. For this purpose, an original method was created, which is based on minimizing the work of cutting forces in the direction of the depth of cutting. The effectiveness of the method has been proved by comparing the RMS values of vibration...
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Optimal spindle speed determination for vibration reduction during ball-end milling of flexible details
PublicationIn the paper a method of optimal spindle speed determination for vibration reduction during ball-end milling of flexible details is proposed. In order to reduce vibration level, an original procedure of the spindle speed optimisation, based on the Liao–Young criterion, is suggested. As the result, an optimal, constant spindle speed value is determined. For this purpose, on-stationary computational model of machining process is...
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Speed and load torque observer application in high-speed train electric drive
PublicationW artykule przedstawiono zastosowanie diagnostyczne obserwatorów prędkości obrotowej i momentu obciążenia w układzie napędowym z silnikiem asynchronicznym. System diagnostyczny jest dedykowany do napędu pociągu szybkiego. Celem diagnostycznym jest monitorowanie stanu czujnika prędkości obrotowej wału silnika oraz układu przeniesienia momentu trakcyjnego. Analiza sygnałów obliczanych w obserwatorach stanu pozwala na wykrycie uszkodzeń...
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Failure analysis of a high-speed induction machine driven by a SiC-inverter and operating on a common shaft with a high-speed generator
PublicationDue to ongoing research work, a prototype test rig for testing high-speed motors/generators has been developed. Its design is quite unique as the two high- speed machines share a single shaft with no support bearings between them. A very high maximum operating speed, up to 80,000 rpm, was required. Because of the need to minimise vibration during operation at very high rotational speeds, rolling bearings were used. To eliminate...
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Reduction of vibration level by the spindle speed optimisation during ball end milling of flexible details
PublicationPraca dotyczy nadzorowania drgań podczas skrawania przedmiotów podatnych frezem kulistym. Przedsatwiono wspomaganą komputerowo procedurę nadzorowania z optymalizacją prędkości obrotowej narzędzia. Przy modelowaniu wykorzystano niestacjonarny model obliczeniowy. Rezultatem modelowania jest układ hybrydowy, w którym oddzielono podukłady: modalny, łączący i strukturalny. Metoda wymaga identyfikacji częstości własnych co może być wykonane...
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The Optimal Spindle Speed Map for Reduction of Chatter Vibration During Milling of Bow Thruster Blade
PublicationW artykule przedstwiono przykład wykorzystania procedury tworzenia mapy optymalnych prędkosci obrotowych w celu ograniczenia drgań samowzbudnych podczas frezowania płata śruby okrętowego steru strumieniowego.
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High-speed memoryless binary/residue converter
PublicationW pracy zaprezentowano nowy szybki konwerter z systemu binarnego do systemu resztowego dla liczb o zakresie do 60 bitów. W konwerterze stosowane są wyłącznie układy kombinacyjne. Algorytm konwertera oparty jest na dodawaniu niezerowych cyfr binarnych reprezentacji kolejnych potęg 2 modulo m. Dodawanie jest realizowane przy użyciu wielooperandowego sumatora CSA oraz sumatora CPA. Suma wyjściowa CPA jest redukowana do zakresu 2m-1...
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Digital structures for high-speed signal processing
PublicationThe work covers several issues of realization of digital structures for pipelined processing of real and complex signals with the use of binary arithmetic and residue arithmetic. Basic rules of performing operations in residue arithmetic are presented along with selected residue number systems for processing of complex signals and computation of convolution. Subsequently, methods of conversion of numbers from weighted systems to...
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Application of speed and load torque observers in high-speed train drive for diagnostic purposes
PublicationW artykule przedstawiono zastosowanie diagnostyczne obserwatorów prędkości obrotowej i momentu obciążenia w układzie napędowym z silnikiem asynchronicznym. System diagnostyczny jest dedykowany do napędu pociągu szybkiego. Celem diagnostycznym jest monitorowanie stanu czujnika prędkości obrotowej wału silnika oraz układu przeniesienia momentu trakcyjnego. Analiza sygnałów obliczanych w obserwatorach stanu pozwala na wykrycie uszkodzeń...
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Kinetic analysis of the stage for a high speed steam turbine
PublicationThis article analyzes possibilites of resonances within a control stage for a high speed steam turbine. This stage hase been based on assembling of a single blade to a rotating disk and increasing of rigidity of the system by using of a bandage. In the analysis will be nd a possiblity of resonance frequency, and mistuning by showing safety working ranges. The calculations have bean used the3D modal and harmonic analysis by the...
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High-speed binary-to-residue converter with improved architecture.
PublicationPrzedstawiono ulepszoną architekturę szybkiego konwertera liczb z systemu binarnego do systemu resztowego dla liczb ze znakiem w kodzie U2. Algorytm konwertera oparty jest o segmentację słowa wejsciowego nasegmenty 4-bitowe. Reszty liczb reprezentowanych przez segmenty sąobliczane poprzez odwzorowanie. Wielooperandowe sumowanie modulo jest realizowane przy użyciu drzewa Wallace'a z segmentacją wektorów wyjściowych oraz finalnego...
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A New Approach For High Speed Data Transmission Monitoring
PublicationW artykule przedstawiono nowatorski sposób monitorowania szybkiej transmisji danych. Technika została zaprezentowana dla przypadku transmisji różnicowej na płycie drukowanej. Cechą szczególną rozwiązania jest możliwość pomiaru jakości transmisji w linii bez konieczności montowania dedykowanych złącz pomiarowych, które mogłyby degradować transmisję.
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FPGA realization of the high-speed binary-to-residue converter
Publicationprzedstawiono architekturę i realizację w technologii fpga konwertera z systemu binarnego do systemu resztowego. algorytm konwertera oparty jest na podziale słowa wejściowego na segmenty 4-bitowe i następnie obliczeniu reszty liczby reprezentowanej przez dany segment, sumowaniu binarnym przy zastosowaniu csa i redukcji modulo w układzie dwuoperandowego sumatora modulo.
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High-speed fpga pipelined binary-to-residue converter
Publicationw pracy przedstawiono architekturę przepływowego konwertera z systemu z uzupełnieniem do 2 z systemu binarnego. zastosowano segmentację słowa wejściowego ze wstępną inwersją dla liczb ujemnych. reszty liczb reprezentowanych przez poszczególne segmenty są obliczane poprzez odczyt z pamięci adresowanej binarną reprezentacją segmentu. otrzymane reszty sumowane są w wielooperandowym sumatorze modulo z korekcją reszty dla liczb ujemnych.pracę...
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Optimization of the spindle speed during milling of large-sized structures with the use of technique of Experiment-Aided Virtual Prototyping
PublicationIn the paper are presented considerations concerning vibration suppression problems during milling of large-sized workpieces with the use of innovative method of matching the spindle speed of cutting tool. It depends on repeatable change of the spindle speed value as soon as the optimal vibration state of the workpiece approaches. The values of dominant “peaks” in the frequency spectra and the Root Mean Square (RMS) values of time...
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An Experimentally Aided Operational Virtual Prototyping to Obtain the Best Spindle Speed during Face Milling of Large-Size Structures
PublicationAbstract: The paper presents an original method concerning the problem of vibration reduction in the general case while milling large-size and geometrically complex details with the use of an innovative approach to the selection of spindle speed. A computational model is obtained by applying the so-called operational approach to identify the parameters of the workpiece modal model. Thanks to the experimental modal analysis results,...
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A technique of experiment aided virtual prototyping to obtain the best spindle speed during face milling of large-size structures
PublicationThe paper presents an original method concerning vibration suppression problem during milling of large-size and geometrically complicated workpieces with the use of novel way of selecting the spindle speed. This consists in repetitive simulations of the cutting process for subsequent values of the spindle speed, until the best vibration state of the workpiece is reached. An appropriate method of obtaining a computational model,...
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Errors of a Linear Current Approximation in High-Speed PMSM Drives
PublicationCurrent sampling techniques and predictive algorithms used in the digital control of electric drives rely on a simple mathematical model that assumes linear current changes upon constant supplying voltages. This paper identifies rotor movement as a factor that makes this assumption invalid when the rotor covers an angular distance of a few tens of degrees during the control interval duration. The errors of the linear current approximation...
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Digitalization of High Speed Craft Design and Operation Challenges and Opportunities
PublicationIn recent years, global demands for safe and sustainable ships led to dramatic changes in the maritime industry. Digitalization is expected to play an important part in the future. This is supported by analysis of the autonomous ships market which shows that digitalization of large ship types such as tankers and container ships is well on track. Although to date designs of autonomous High-Speed Craft (HSC) have been developed,...
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High-speed residue-to-binary converter based on the Chinese RemainderTheorem.
PublicationPrzedstawiono szybki konwerter z systemu resztowego do systemu binarnego dla modułów 5-bitowych oparty o chińskie twierdzenie o resztach. Projekcje ortogonalne są generowane przy użyciu odwzorowania realizowanego przy zastosowaniu funkcji logicznych pięciu zmiennych. Wartość wyjściowa jest obliczana przy użyciu drzewaWallace'a z segmentacją wektorów wyjściowych i redukcją do 2M, M zakres liczbowy systemu oraz efektywny finalny...
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High-speed binary-to-residue converter with the reduced input layer
Publicationprzedstawiono architekturę szybkiego konwertera z systemu binarnego do systemu resztowego dla modułów 5-bitowych. Algorytm konwersji oparty jest na dodawaniu binarnym reszt potęg liczby 2 obliczonych modulo m i redukcji modulo m sumy dla poszczególnych modułów bazy systemu resztowego. Warstwa wejciowa konwertera jest redukowana poprzez wykorzystanie wspólnych elementów układu dla odpowiednio zestawionych par modułów.
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Sensorless Startup of Super High Speed Permanent Magnet Motor
PublicationCelem artykułu jest przedstawienie metody bezczujnikowego rozruchu wysokoobrotowego silnika z magnesami trwałymi. Zastosowano dwa typy metod sterowania. W pierwszej fazie rozruchu zastosowano metodę sterowania prądem, następnie przełączono do trybu sterowania wektorowego. Przy sterowaniu wektorowym zostały użyte: rozszerzony filtr Kalmana (EKF) oraz alternatywny Bezśladowy Filtr Kalmana (UKF) jako obserwatory prędkości obrotowej....
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Sensorless control of high speed permanent-magnet synchronous motor
PublicationW artykule przedstawiono metodę bezczujnikowego sterowania szybkoobrotowym silnikiem z magnesami trwałymi. Pokazano działanie układu sterowania opartego na filtrze kalmana (EKF) jako obserwatora prędkości obrotowej.
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Improvement of microstructure and mechanical properties of high dense sic ceramics manufactured by high-speed hot pressing
PublicationNon-oxide ceramics possess high physical-mechanical properties, corrosion and radiation resistance, which can be used as a protective materials for radioactive wastes disposal. The aim of the present study was the manufacturing of high density SiC ceramics with advanced physical and mechanical parameters. The high performance on the properties of produced ceramics was determined by the dense and monolithic structure. The densified...
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Induction motor control application in high-speed train electric drive
PublicationThe chapter presents an application of induction motor mechanical speed and load torque observers in high-speed train drives. The observers are applied for a 1.2-MW electric drive with an induction motor. The goal of using such observers is to utilize computed variables for diagnostic purposes of speed sensors and torque transmission system. The concept of diagnostic system is presented in this paper, and proper criteria are proposed....
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A New Coupler Concept for Contactless High-Speed Data Transmission Monitoring
PublicationThis paper presents a new concept of a couplerthat can be applied to high-speed data transmission contactlessmeasurements. The proposed approach is dedicated for differentialsignal transmission monitoring in microstrip coupled lineson printed circuit boards (PCBs). The coupler, produced on aseparate PCB, is overlayed on the transmission line with thedifferential signal and delivers decoupled differential signal tothe main measurement...
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Measurements of High-Speed Data Transmission Radio Link for Special Applications
PublicationIn the article measurements of high-speed data transmission radio link for special applications were presented. Build measurement stand, measurement scenario and obtained results were briefly described. All conducted research work took place in real maritime environment.
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ANALYSIS OF THE POSSIBILITIES OF HIGH SPEED SHAFT BEARING SYSTEM DURABILITY INCREASE
PublicationDuring the operation of wind turbines with a gearbox of traditional configuration, a high failure rate of high-speed shaft bearings is observed. Such a high failures frequency is not reflected in standard bearing durability calculation methods, which can be attributed to atypical failure mechanism. To avoid observed problems in the 1.5 MW wind turbine, the modification of the existing bearing system is proposed. Multiple options,...
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High-Speed Serial Embedded Deterministic Test for System-on-Chip Designs
PublicationThe paper presents a high-speed serial interface between external tester and Embedded Deterministic Test (EDT) compression logic hosted by SoC designs. With only a single bidirectional link, the system is capable of feeding distributed heterogeneous cores with hundreds of test channels. Moreover, it synergistically supports EDT bandwidth management to improve the overall test performance. A detailed study indicates a high potential...
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The contactless method of chip-to-chip high-speed data transmission monitoring
PublicationThis paper presents a technique of decoupling differential signals transmitted in a pair of microstrip lines on a printed circuit board (PCB), using dedicated coupler for high speed data transmission monitoring in chip-to-chip interconnections. The coupler used for signal probing is overlayed on the pair of microstrip lines under test, and provides a signal to the next blocks of the measurement system without disturbing transmission...
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Analysis of Failures of High Speed Shaft Bearing System in a Wind Turbine
PublicationDuring the operation of wind turbines with gearbox of traditional configuration, consisting of one planetary stage and two helical stages high failure rate of high speed shaft bearings is observed. Such a high failures frequency is not reflected in the results of standard calculations of bearing durability. Most probably it can be attributed to atypical failure mechanism. The authors studied problems in 1.5 MW wind turbines of...
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Synchronized six-step voltage generation in high-speed PMSM drive
PublicationSynchronized voltage generation has already been considered in the context of pulse width modulation (PWM). References prove that synchronized PWM substantially decreases subharmonics in inverter output voltage when operating with low switching-to-fundamental frequency ratio. This paper identifies problems of unsynchronized voltage generation in electric drives under six-step inverter operation. Guidelines for the synchronization...
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Integrated Control in High-Speed Networks Using Constrained Model Predictive Control
PublicationThis paper studies congestion control in high-speed communication networks using Model Predictive Control (MPC). Network traffic is assumed to consist of best-effort and priority traffic sources. An integrated controller consisting of two control parts is designed. The controller calculates the capacity for priority sources and the input rate of best-effort sources. MPC is desirable as it can take into account the constraints on...
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An improved high-speed residue-to-binary converter based on the chinese remainder theorem
Publicationw pracy zaprezentowano nowy szybki konwerter z systemu resztowego do systemu binarnego. Projekcje ortogonalne wyznaczane są przy użyciu funkcji logicznych pięciu zmiennych. Suma projekcji obliczana jest z zastosowaniem drzewa Wallace'a. Wektor sumy i wektor przeniesienia są dzielone na segmenty tak aby liczba reprezentowana łącznie przez obydwa segmenty o młodszych wagach nie przekraczała zakresu systemu resztowego,M. Bity segmentów...
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Fpga implementation of the two-stage high-speed fir filter in residue arithmetic
Publicationw pracy przedstawiono implementację szybkiego, dwustopniowego kaskadowego filtru fir w technologii fpga z użyciem arytmetyki resztowej. zastosowanie arytmetyki resztowej pozwala na uzyskanie dużych częstotliwości potokowania w związku z użyciem małych mnożników. zalety arytmetyki resztowej są ograniczane w pewnym stopniu koniecznością wykonywania skalowania po pierwszym stopniu filtru celem uniknięcia nadmiaru arytmetycznego. w...
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FPGA realization of high-speed multi-stage FIR filter in residue arithmetic
PublicationW pracy przedstawiono implementację szybkiego wielostopniowego, kaskadowego filtru FIR w technologii FPGA. Zastosowanie arytmetyki resztowej pozwala na uzyskanie dużych częstotliwości próbkowania w zwiżaku z użyciem małych mnożników. Zalety wynikające z uzycia arytmetyki resztowej sa w pewnym stopniu ograniczne koniecznością wykonania skalowania przy kaskadowym połaczeniu filtrów FIR, tak aby uniknąć nadmiaru arytmetycznego. W...
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Simulation and Experiments of High Speed Machining Vibration Monitoring with Variable Spindle Velocity
PublicationArtykuł poświęcony jest nadzorowaniu drgań wirujących narzędzi podczas obróbki szybkościowej na nowoczesnych centrach frezarskich. Przeprowadzono analizę dynamiki procesu skrawania smukłym frezem kulistym. W celu zredukowania drgań zastosowano, z powodzeniem, zmienną prędkość obrotową narzędzia. Badania symulacyjne dotyczące efektywności proponowanej metody zostały potwierdzone wynikami badań eksperymentlanych na frezarce Alcera...
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DYNAMIC ANALYSIS OF THE RAILWAY BRIDGES IN POLAND WITH REGARDS TO HIGH-SPEED TRAINS PASSAGE ADJUSTMENT
PublicationThe dynamic analysis of the railway bridge in Tczew was carried out in the article as an example of such bridges adaptation suitability to handle high-speed trains. Calculations of railway bridges are greatly complicated and labor-consuming. The bridge model and a rolling stock passage simulation were developed in the SOFISTIK software. Three types of elements were used for the correct mapping of the structure in the calculation...
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Effect of Pendolino high-speed rail on the structure of buildings located the proximity of the railway tracks
PublicationThe following research focuses on the dynamic analysis of the impact of the high-speed train inducted vibrations on the structures located near railway tracks. The office complex chosen as the subject of calculations is located in the northern part of Poland, in Gdańsk, in the proximity of Pendolino, the high speed train route. The high speed trains are the response for the growing needs for more efficient railway system. However...
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Impact of digital signal processing on FOC current feedback in high-speed PMSM drive
PublicationIn applications where size and weight of the electric motor are among major design concerns, Permanent Magnet Synchronous Motors (PMSMs) with wide operational speed-range are commonly preferred. Due to limited inverter switching frequency, high-speed operation of a drive results in a low ratio between the switching frequency and the fundamental frequency of motor voltage. Such operating conditions have been recently identified...
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Research and analysis of high-speed data transmission radio link designed for maritime environment
PublicationIn these article the realization of digital radio link for high-speed data transmission was presented. Its concept and practical realization, using USRP devices from National Instruments, were described. Developed software for generation and reception of digital signals in baseband, including description of modulation types, and time and frequency synchronization mechanisms, was presented. Moreover, an operation of designed radio...
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Research and Analysis of High-Speed Data Transmission Radio Link Designed for Maritime Environment
PublicationIn these article, the realization of digital radio link for high-speed data transmission was presented. Its concept and practical realization, using USRP devices from National Instruments, were described. Developed software for generation and reception of digital signals in baseband, including description of modulation types, and time and frequency synchronization mechanisms, was presented. Moreover, an operation of designed radio...
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Torque transmission diagnostic system for high-speed train using state-space observer
PublicationW artykule przedstawiono zagadnienie diagnostyki czujnika prędkości silnika i przekładni mechanicznej pociągu. W celach diagnostycznych zastosowano obserwatory stanu do obliczania prędkości obrotowej silnika i momentu obciążenia. Analiza chwilowych wartości obliczonej prędkości obrotowej oraz momentu obciążenia pozwala na diagnozowanie stanu układu transmisji momentu trakcyjnego. Zaprezentowano wyniki badań symulacyjnych i eksperymentalnych...
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FPGA realization of the high-speed residue-to-binary converter based on chinese remainder theorem
PublicationW pracy przedstawiono architekturę, realizację FPGA oraz symulację numeryczną na poziomie bitowym szybkiego konwertera z systemu resztowego do systemu binarnego dla modułów 5-bitowych opartego na chińskim twierdzeniu o resztach. Algorytm konwertera obejmuje obliczanie projekcji ortogonalnych poprzez odczyt pamięci oraz sumowanie modulo M realizowane dwustopniowo, pierwszy stopień oparty o sumatory CSA umożliwia redukcję do zakresu...
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FPGA realization of the high-speed residue-to-binary converter based on the Chinese Remainder Theorem
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ALTERNATIVE, DIRECT SYNTHESIS METHOD OF THE CERAMIC SOLID SOLUTIONS BASED ON BaTiO3 THROUGH A HIGH ENERGY BALL MILLING
PublicationPolycrystalline samples BaTiO3 and the solid solutions Ba0.9Sr0.1TiO3, Ba0.9Sr0.1Ti0.9Sn0.1O3, Ba0.9Sr0.1Ti0.8Sn0.2O3 were obtained by means of a mechanochemical treatment based on the high-energy ball milling technique and next a high temperature solid state reaction method. The influence of synthesis condition on microstructural, dielectric and ferroelectric properties of obtained solid solutions were investigated. The structure...
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Optimization of clamping stiffness during milling of high-dimensional structures with the use of techniques of experiment – aided virtual prototyping
PublicationThe subject of this paper is a method of searching for conditions of minimizing the vibration level of a tool-high dimensional flexible workpiece, at unchangeable technological parameters of the machining process. It depends on repeatable change of the values of the stiffness coefficients as soon as an optimal vibration state of the workpiece approaches. There are assessed the values of dominant ”peaks” in the frequency spectra...
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Study of the influence of high-energy milling time on the Cu–13Al–4Ni alloy manufactured by powder metallurgy process
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Implementation of high-speed data transmission technological demonstrator using software defined radio technology
PublicationIn the article implementation of high-speed data transmission technological demonstrator using software defined radio technology is presented. A system architecture design including asymmetric framing transmission organization, which differs from the ones used in cellular systems is described. The construction of technological demonstrator consisting of management unit, radio unit and programmable multithreaded software performing...
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Implementation of high-speed data transmission technological demonstrator using software defined radio technology
PublicationIn the article implementation of a high-speed data transmission technological demonstrator using software defined radio technology is presented. A system architecture design including asymmetric framing transmission organization, which differs from the ones used in cellular systems is described. The construction of technological demonstrator consisting of a management unit, radio unit and programmable multi-threaded software performing...
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High-Speed Binary-to-Residue Converter Design Using 2-Bit Segmentation of the Input Word
PublicationIn this paper a new approach to the design of the high-speed binary-to-residue converter is proposed that allows the attaining of high pipelining rates by eliminating memories used in modulo m generators. The converter algorithm uses segmentation of the input binary word into 2-bit segments. The use and effects of the input word segmentation for the synthesis of converters for five-bit moduli are presented. For the number represented...
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RNS reverse high-speed converter with quasi-regular structure based on the Chinese Remainder Theorem
PublicationPrzedstawiono dwie nowe architektury szybkiego konwertera z systemuresztowego do systemu binarnego oparte o chińskie tw. o resztach. Zastosowano nowe struktury 4-operandowych sumatorów modulo 2M. Pierwsza ze struktur oparta jest o wstępne sumowanie najstarszych bitów wektorów sumy i przeniesienia na wyjściu sumatora CSA, natomiast druga o bezpośrednie wykrywanie przekroczenia 2M. Konwerter wykorzystujący drugą ze struktur charakteryzuje...
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Considerations about the applicability of the Reynolds equation for analyzing high-speed near field levitation phenomena
Publicationequation for analyzing near field levitation (NFL) phenomena. Two separate approaches were developed, experimentally verified, and applied to meet the research objective. One was based on the Reynolds equation and the other was based on general conservation equations for fluid flow solved using computational fluid dynamic (CFD). Comparing the calculation results revealed that, for certain operating conditions, differences in the...
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Study of prototype multi-pole non-salient field winding for high speed brushless synchronous generator
PublicationIn this paper a non-salient field winding for a brushless synchronous generator working with high speed in an autonomous energy generation system (e.g. airplane power grid) has been presented. A conception of a six-pole cylindrical-rotor with distributed field winding has been proposed. Comparison study of salient and prototype non-salient field winding has been carried out. Chosen simulation and measurement results of the generator...
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Modeling the impact of rotor movement on non-linearity of motor currents waveforms in high-speed PMSM drives
PublicationMotor current measurement techniques as well as predictive control algorithms for electric drives rely on an assumption of linear motor currents changes resulting from constant inverter output voltages. Recent research has reported that this assumption does not hold in motors with short electrical time constant, and in drives whose rotor position advances substantially during a control period. This paper proposes a simulation model...
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Research of low-speed high torque planet motors supplied with oil-in-water emulsion as working liquid.
PublicationWiększość hydraulicznych układów napędowych obecnie jest zasilanych olejami. Ale olej jako medium robocze nie może być stosowany wszędzie tam, gdzie istnieje ryzyko pożaru. dlatego też są stosowane trudnopalne i niepalne ciecze hydrauliczne ja: emulsje, mikroemulsje i roztwory. W referacie opisano stanowisko badawcze zaprojektowane i zbudowane w Katedrze Hydrauliki i Pneumatyki PG, przedstawiono wyniki badań hydraulicznego silnika...
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Modelling of the High Speed Multi-Pole Synchronous Generator for Application in More Electric Aircraft Power Systems
PublicationIn this paper different models of the synchronous generator are presented. The simulation results compared with the measurements are shown. Certain physical phenomena are included in described models for the porpoise of adequate analysis of the more electric aircraft power system. For different modelling levels, such as functional level or behavioural level, different physical phenomena have been included. Simulation results for...
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Appliance of High Speed Camera during Industrial Exploitation on the Example of Static and Dynamic Tests of Steel Probes
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High-Performance Face Milling of 42CrMo4 Steel: Influence of Entering Angle on the Measured Surface Roughness, Cutting Force and Vibration Amplitude
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State-of-the-art framework for high-speed camera and photogrammetric use in geometry evaluation of prestressed concrete failure process
PublicationPrestressed structures are a key to the realization of the boldest architectural ideas, regardless of shape complexity, great height and large span. A characteristic feature of the prestressed structure is the better use of concrete material properties by insertion of internal forces. The internal forces are opposed to external loads effects (forces and deformations of structure). Prestressed reinforced concrete beams are characterized...
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Structure and properties of the Ti+Ti(C,N) coatings obtained in the PVD process on sintered high speed steel
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Modeling the impact of discretizing rotor angular position on computation of field-oriented current components in high speed electric drives
PublicationModern drives consist of alternating current electric motors, and the field-oriented control (FOC) of such motors enables fast, precise, and robust regulation of a drive's mechanical variables such as torque, speed, and position. The control algorithm, implemented in a microprocessor, requires feedback from motor currents, and the quality of this feedback is essential to a drive's control properties. Motor phase currents are sampled...
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THE INFLUENCE OF HOUSING ARRANGEMENT AND INTERFERENCE ON PRELOAD AND THEORETICAL LIFETIME OF A SYSTEM OF TAPER ROLLER BEARINGS OF A HIGH SPEED SHAFT OF A WIND TURBINE GEARBOX
PublicationA system of two taper roller bearings can carry loads with a high ratio of axial load to radial load. Such a system was proposed for a wind turbine gearbox following the poor durability of original bearing design with the aim of increasing durability. Because of size limits, a proposed system is composed of two different taper roller bearings. Standard manufacturers’ catalogues do not provide information on recommended preload...
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High-Speed Videoendoscopy Enhances the Objective Assessment of Glottic Organic Lesions: A Case-Control Study with Multivariable Data-Mining Model Development
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Volume optimization of high-speed surface-mounted permanent magnet synchronous motor based on sequential quadratic programming technique and analytical solution
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VIBRATION SURVEILLANCE DURING MILLING OF FLEXIBLE DETAILS WITH A USE OF THE ACTIVE OPTIMAL CONTROL
PublicationThe main goal of modern machining operations is to achieve increasingly better performance. High Speed Machining and/or High Performance Cutting, despite a lot of advantages, have also some drawbacks, for example, a possibility of losing stability and development of self-excited chatter vibration. This paper presents an approach of vibration surveillance during high speed milling with a use of active optimal control. Non-stationary...
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A modified method of vibration surveillance by using the optimal control at energy performance index
PublicationA method of vibration surveillance by using the optimal control at energy performance index has been creatively modified. The suggested original modification depends on consideration of direct relationship between the measured acceleration signal and the optimal control command. The paper presents the results of experiments and Hardware- in-the-loop simulations of a new active vibration reduction algorithm based on the energy...
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Vibration Surveillance System with Variable Stiffness Holder for Milling Flexible Details
PublicationEfficient milling of the flexible details (i.e. rotor blades, thin-walled elements) using slender ball-end tools is a difficult task due to possibility of vibration occurrence. Because of the existence of certain conditions (small depths of cutting, regeneration phenomena), cutting process may lose stability and self-excited chatter vibration may appear. Frequency of the chatter vibration is close to dominant natural frequency...
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Modelling and Simulation of a New Variable Stiffness Holder for Milling of Flexible Details
PublicationModern industry expectations in terms of milling operations often demand the milling of the flexible details by using slender ball-end tools. This is a difficult task because of possible vibration occurrence. Due to existence of certain conditions (small depths of cutting, regeneration phenomena), cutting process may become unstable and self-excited chatter vibration may appear. Frequency of the chatter vibration is close to dominant...
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Simplified Map-based Selection of Optimal Spindle Speeds When Milling Complex Structures
PublicationIn the paper a method for selecting optimal spindle speeds for complex structures during milling operations is presented. It is based on the selection of the spindle speed in accordance with a simple equation resulting from the minimisation of vibration energy, which leads to the minimisation of the work of cut-ting forces presented in previous elaborations by the authors [1]. Optimal spindle speeds are obtained for many points...
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Ball milling induced borophene flakes fabrication
PublicationTo fill the knowledge gap for borophene, as the youngest member of the two-dimensional (2D)nanomaterials family, a facile, cost effective, scalable and reproducible fabrication route is still stronglyrequired. Among so far studied techniques the potential of pure mechanical processes such as ballmilling is not explored yet. Therefore, in this contribution, we explore the efficiency...
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Vibration surveillance for efficient milling of flexible details fixed in adjustable stiffness holder
PublicationThe paper presents the results of research related to the possibility of using an intelligent workpiece holder with adjustable stiffness, during end milling process. Machining a one side supported flexible workpiece will be performed with constant spindle speed and feed speed. In order to avoid hazardous vibration, stiffness of the especially designed spring (mounted in a workpiece holder) will be modified off-line. In order to...
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Experimental research of the effect of face milling strategy on the flatness deviations
PublicationIn this paper the dependencies between face milling strategy of EN AW6082-T6 aluminum alloy samples, with difference thicknesses (6, 8, and 12 mm) and two cold rolling directions, and flatness deviations were presented. Three strategies of milling included different proportions of material removed from both sides of the plates. This approach allowed to control the proportions of residual surface stresses on both sides of the specimens,...
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Minimization of vibrations during milling of flexible structures using mechatronic design techniques
PublicationThe paper presents an innovative effective method of minimizing vibrations during milling of flexible structures, using a new vibration suppression method based on a workpiece holder with adjustable support stiffness. The proposed method is rooted in mechatronic design techniques, which can become a standard procedure for optimizing the milling process.
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Adjusting the Stiffness of Supports during Milling of a Large-Size Workpiece Using the Salp Swarm Algorithm
PublicationThis paper concerns the problem of vibration reduction during milling. For this purpose, it is proposed that the standard supports of the workpiece be replaced with adjustable stiffness supports. This affects the modal parameters of the whole system, i.e., object and its supports, which is essential from the point of view of the relative tool–workpiece vibrations. To reduce the vibration level during milling, it is necessary to...
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THE EFFECT OF ALTERNATIVE CUTTER PATHS ON FLATNESS DEVIATIONS IN THE FACE MILLING OF ALUMINUM PLATE PARTS
PublicationIn this paper the relationships between the alternative machining paths and flatness deviations of the aluminum plate part, were presented. The flatness tolerance of the main surface of the plate part has crucial meaning due to the assembly requirement of piezoelectric elements on the radiator. The aluminum bodies under investigation are the base part of the radiators with crimped feathers for the train industry. The surface of...
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FPGA Based Real Time Simulations of the Face Milling Process
PublicationThe article presents a successful implementation of the milling process simulation at the Field-Programmable Gate Array (FPGA). By using FPGA, very rigorous Real-Time (RT) simulation requirements can be met. The response time of the FPGA simulations is significantly reduced, and the time synchronization is better than in a typical RT system implemented in software. The FPGA-based approach is characterized by enormous flexibility...
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Surface Roughness Evaluation in Thin EN AW-6086-T6 Alloy Plates after Face Milling Process with Different Strategies
PublicationLightweight alloys made from aluminium are used to manufacture cars, trains and planes. The main parts most often manufactured from thin sheets requiring the use of milling in the manufacturing process are front panels for control systems, housing parts for electrical and electronic components. As a result of the final phase of the manufacturing process, cold rolling, residual stresses remain in the surface layers, which can influence...
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The effect of thermal modification on the quality of the milled surface of beech and pine wood
PublicationThe article deals with the effect of thermal modification on the quality of the created surface during milling on CNC milling cutters. The quality of the created surface is evaluated based on surface roughness, specifically its roughness parameter Ra. The observed surface is created by a shank cutter with a diameter of 20 mm and three cutting edges in a spiral at a standard speed of 18,000. min-1. The article compares thermally...
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Ball milling treatment of Mn3O4 regulates electron transfer pathway for peroxymonosulfate activation
PublicationHeterogeneous metal catalysts have attracted considerable interest in advanced oxidation processes (AOPs) for wastewater treatment by activating peroxymonosulfate (PMS). However, it remains challenging to the rational design of efficient reaction pathway for high-performance contaminants removal by regulating the inherent structure of metal oxides. Herein, a high-energy ball milling method was employed to modulate the electronic...
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A method of predicting the best conditions for large-size workpiece clamping to reduce vibration in the face milling process
PublicationThe paper presents an innovative method of solving the problem of vibration suppression during milling of large-size details. It consists in searching for the best conditions for clamping the workpiece based on a rapid modal identification of the dominant natural frequencies only and requires repetitive changes in the tightening torque of the clamping screws. Then, by estimating the minimum work of the cutting forces acting in...
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The clamping selection method to reduce the vibration of large-size workpieces during the face milling process
PublicationThe article introduces a method for selecting the best clamping conditions to obtain vibration reduction during milling of large-size workpiece. It is based on experimental modal analysis performed for a set of assumed, fixing conditions of a considered workpiece to identify Frequency Response Functions (FRFs) for each tightening torque of the mounting screws. Simulated plots of periodically changing nominal cutting forces are...
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Convenient and efficient N-methylation of secondary amines under solvent-free ball milling conditions
PublicationIn the present work, we report the development of a rapid, efcient, and solvent-free procedure for the N-methylation of secondary amines under mechanochemical conditions. After optimization of the milling parameters, a vibrational ball mill was used to synthesize 26 tertiary N-methylated amine derivatives in a short time of 20 min (30 Hz frequency) and high yields ranging from 78 to 95%. An exception was compounds having a hydroxyl...
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An investigation of microstructural basis for corrosion behavior of Al-CNT composites fabricated by SPS
PublicationIn this research effect of the addition of multi-wall carbon nanotubes (MWCNTs) as additive powder on microstructure and corrosion behavior of fabricated Al-CNT composites was studied. The aluminum powder and CNTs were mixed with high energy planetary ball-mill. It is observed that by increasing milling time, the uniformity of CNTs on aluminum matrix and consequently corrosion resistance of Al-CNT composite is increased. On the...