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Abstrakt

Artykuł jest próbą analizy dyskursu przestrzenno-pedagogicznego na gruncie niemieckiej pedagogiki społecznej. Stanowi wycinek rozważań na temat zmiany w paradygmacie myślenia o miejscu/przestrzeni (spatial turn), jako kategoriach pedagogicznych. Autorki szukają odpowiedzi na pytanie, czym jest przestrzeń i miejsce oraz jakimi pojęciami w zakresie refleksji nad miejscem/przestrzenią operuje niemiecka pedagogika społeczna. Tekst przybliża między innymi relacyjną koncepcję przestrzeni Martiny Löw, jej dwuznaczność oraz pojęcie spacingu. Aktywne wytwarzanie przestrzeni miejskiej oraz przestrzenny wymiar relacji i jego dynamika poddane są dyskusji. Artykuł prezentuje również głosy krytyczne, dotyczące między innymi transdyscyplinarności przestrzeni oraz pracy socjalnej zorientowanej na przestrzeń socjalną. Stanowi zachętę do pogłębionych, międzynarodowych analiz teorii przestrzenno-pedagogicznych.

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Autorzy i Afiliacje

Jacqueline Puchert
Aleksandra Kurowska-Susdorf

Abstrakt

The transfer function (TF) method is presently a well-known method used to detect various types of winding damage in power transformers. Although abundant research has been done on this subject using laboratory windings as test objects, it is hard to find one, whose test objects are actual large-power transformer windings. Hence, a 400 kV disc winding consisting of 86 discs is used in this paper to study turn-to-turn short circuit with the help of the TF method. To evaluate the effects of this type of fault on TF curves, some mathematical comparison algorithms are used in this research.

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Autorzy i Afiliacje

Ebrahim Rahimpour
Stefan Tenbohlen

Abstrakt

U-turn lanes eliminate left turns at intersections and allow the manoeuvre to be made via median crossovers beyond the intersection. However, there are many situations where road infrastructures are characterized by the reduced width of the median. It is clear that, in such situations, we must adopt design criteria that take into account limitations imposed by the width of the cross-section of the road. This is the reason why it is necessary to adopt design solutions which expect a complete reorganization of the road section affected by the insertion of U-turns. In this paper, we intend to propose original guidelines for U-turn lane design, suitable to guarantee both the necessity to offer a high level of functionality of the road sections to be implemented by U-turns, and the principles of safety in order to reduce unsafe conditions during inversion manoeuvres as much as possible.

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Autorzy i Afiliacje

N. Distefano
S. Leonardi

Abstrakt

In the article we address matters related to the stability of motion of the car subjected to the external lateral force. We show the possibility to compensate the effect of the external forces my means of the steering wheel angle. We have carried out the analysis for bicycle scheme vehicle and four-wheel model according to linear and nonlinear drift hypothesis. We have considered influence of speed of the car and size of external side force for the period of transition processes of stabilization of the movement.
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Autorzy i Afiliacje

V. Verbitskii
R. Kuliev
K. Kravchenko

Abstrakt

Realizowany od lat 80. XX w. program „odbudowy miasta” zakłada uspołecznienie programów reform i polityki miejskiej. Celem artykułu jest ukazanie, jak program Krajowej Polityki Miejskiej przechwytuje i asymiluje ideały „bycia razem” (wspólnego bycia) wypracowane przez ruchy miejskie. Rządowe programy widzą w społeczeństwie „innowację” i nieuwzględniany wcześniej potencjał w planach rozwojowych. Dokonują „operacjonalizacji” ideałów i postulatów ruchów miejskich w taki sposób, by uczynić społeczeństwo nowym zasobem rozwoju ekonomicznego. Asymilacja i translacja roszczeń oraz ideałów ruchów miejskich przez programy rządowe zarządzania miastem staje się elementem nowej politycznej racjonalności.

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Autorzy i Afiliacje

Małgorzata Jacyno

Abstrakt

In intra-enterprise logistics and automation of manufacturing processes general a rising productivity by high flexibility is required. Existing transportation systems exclusively use two-dimensional track sections, because they can be served with standard drives. Because of these simple structures the transport speed is limited and thereby also the throughput. In this paper now a modular transportation system is presented which could reach higher speeds with a direct drive and the use of centrifugal force compensating curves. Simultaneously the system also can change the altitude. All this succeeds with the integration of three-dimensional track sections. Therefore a two piped guiding system with a long stator linear motor was designed. To combine the linear motor with the three dimensional track special stator elements were developed which allow a bending of the stator to follow the route course. The current work deals with the implementation of a mechanical passive switch, which is operated by the electromagnetic forces of the linear motor. So no additional mechanical actors or a separate electromagnetic system are necessary.
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Autorzy i Afiliacje

Christoph Löffler
Wolf-Rüdiger Canders

Abstrakt

This text describes the contemporary teoretical refelection on the place of ethics in historical discourse. It is focused on considering the effect of arguments of ethical tum in humanities on the debate concern with historical representations of Shoah.
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Autorzy i Afiliacje

Jakub Muchowski
ORCID: ORCID

Abstrakt

The presence of an open-circuit fault subjects a three-phase induction motor to severely unbalanced voltages that may damage the stator windings consecutively causing total shutdown of systems. Unplanned downtime is very costly. Therefore, fault diagnosis is essential for making a predictive plan for maintenance and saving the required time and cost. This paper presents a model-based diagnosis technique for diagnosing an open-circuit fault in any phase of a three-phase induction motor. The proposed strategy requires only current signals from the faulty machine to compare them with the healthy currents from an induction motor model. Then the errors of comparison are used as an objective function for a genetic algorithm that estimates the parameters of a healthy model, which they employed to identify and localize the fault. The simulation results illustrate the behaviours of basic parameters (stator and rotor resistances, self-inductances, and mutual inductance) and the number of stator winding turn parameters with respect to the location of an open-circuit fault. The results confirm that the number of stator winding turns are the useful parameters and can be utilized as an identifier for an open-circuit fault. The originality of this work is in extracting fault diagnosis features from the variations of the number of stator winding turns.

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Autorzy i Afiliacje

Raya A.K. Aswad
Bassim M.H. Jassim

Abstrakt

The following paper presents the players profiling methodology applied to the turn-based computer game in the audience-driven system. The general scope are mobile games where the players compete against each other and are able to tackle challenges presented by the game engine. As the aim of the game producer is to make the gameplay as attractive as possible, the players should be paired in a way that makes their duel the most exciting. This requires the proper player profiling based on their previous games. The paper presents the general structure of the system, the method for extracting information about each duel and storing them in the data vector form and the method for classifying different players through the clustering or predefined category assignment. The obtained results show the applied method is suitable for the simulated data of the gameplay model and clustering of players may be used to effectively group them and pair for the duels.
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Autorzy i Afiliacje

Piotr Bilski
1
ORCID: ORCID
Izabella Antoniuk
2
ORCID: ORCID
Rafał Łabędzki
3

  1. Warsaw University of Technology, Poland
  2. Warsaw University of Life Sciences, Poland
  3. SGH Warsaw School of Economics, Poland

Abstrakt

This article presents the problem of understanding Heideggerian ‘turn’ (Kehre) in the context of the most important aspects of his later philosophy. Since Heidegger had written (secretly) Contributions to Philosophy, he departed from his original philosophical assumptions, which had been presented in Being and Time. Heidegger’s turn was conceived as a discovery of truth of Being, as a project of another beginning, as proper asking about Being as such, as well as a discovery of a hidden aspect of being that is revealed in an event (‘enowning’).

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Autorzy i Afiliacje

Jacek Surzyn

Abstrakt

Etyka gospodarcza – wraz z innymi etykami stosowanymi – poszukuje podstaw ważnościowych swoich sądów. O możliwości wykorzystania jej w procesie mediacji pomiędzy uczestnikami życia gospodarczego decydują przecież argumenty uzasadnia-jące jej werdykty. Muszą one być przekonujące oraz spełniać wymóg bezstronności. Owszem, w ich pozyskiwaniu pomocna jest etyka filozoficzna. Wobec wielości jej propozycji oraz ich niedostatecznego epistemologicznego ugruntowania akcent pada na te z nich, którym towarzyszy metaetyczna rekomendacja. Tu zaś wybór narzędzi ulega znacznemu ograniczeniu. Z tego powodu, poszukiwania etycznej miary, zachowującej walory aplikacyjne, kontynuowane są w sferze kultury. Tymczasem to rozszerzenie wymaga ostrożności. Próżno szukać w kulturze gotowej odpowiedzi na pytanie, jak być powinno. Kultura, rzecz jasna, zawiera takie odpowiedzi. Zawiera ich jednak więcej, niż spodziewałby się tego etyk poszukujący w jej obszarze rozwiązania nurtujących go problemów. Okolicznością utrudniającą owe poszukiwania są zmiany w kulturze Zachodu, dokonujące się od połowy XX wieku. Ich wieloaspektowość sprawia, że nie poddają się one systematyzacji podporządkowanej zasadzie koherencji. Domniemanie dotyczące złożoności i niejednorodności przekonań normatywnych żywionych przez społeczeństwa zachodnie potwierdza m.in. analiza procesów zapoczątkowanych przez zwrot performatywny. Celem artykułu jest wyjaśnienie, dlaczego świat wartości kulturowych, pomimo wielości praktyk nadawania im znaczenia, zasadnie aspiruje do miana normatywnego fundamentu życia zbiorowego, w tym życia gospodarczego.

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Autorzy i Afiliacje

Przemysław Rotengruber

Abstrakt

Production waste is one of the major sources of aluminium for recycling. Depending on the waste sources, it can be directly melted in furnaces, pre-cleaned and then melted, or due to the small size of the material (powder or dust) left without remelting. The latter form of waste includes chips formed during mechanical cutting (sawing) of aluminium and its alloys. In this study, this type of chips (with the dimensions not exceeding 1 mm) were melted. The obtained results of laboratory tests have indicated that even chips of such small sizes pressed into cylindrical compacts can be remelted. The high recovery yield (up to 94 %) and degree of metal coalescence (up to 100 %) were achieved via thermal removal of impurities under controlled conditions of a gas atmosphere (argon or/and air), followed with consolidation of chips at a pressure of minimum 170 MPa and melting at 750 oC with NaCl-KCl-Na3AlF6 salt flux.

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Autorzy i Afiliacje

P. Palimąka

Abstrakt

The purpose of this scientific paper is to follow the influence of thermal galvanizing, as a technological process on the quality of the galvanized surface. The galvanizing technology used and studied involves at the end of the process, the removal of excess zinc from the surface by centrifugation. The zinc layer will be lower than that of simple immersion galvanizing. The measurements were performed following the roughness of the machined surface on a five-Section specimen – each Section being processed with a different cutting regime. The results were analyzed after each operation. The first measurements were made after the turning operation, followed by measurements made after pickling and fluxing and then after thermal galvanizing. Based on the results obtained, the aim was to set up a range of best roughness at which the galvanized part should have a commercial appearance and be made with a cost-effective cutting regime in terms of costs.
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Autorzy i Afiliacje

Sandor Ravai-Nagy
1
ORCID: ORCID
Alina Bianca Pop
1
ORCID: ORCID
Marcin Nabiałek
2
ORCID: ORCID
Costin Alexandru
3
ORCID: ORCID
Mihail Aurel Țîțu
4
ORCID: ORCID

  1. Technical University of Cluj-Napoca, Northern Un iversity Cent re of Baia Mare, Faculty of Engineering – Department of Engineering and Technology Management , 62A, Vict or Babes Street, 430083, Baia Mare, Maramures, Romania
  2. Częstochowa University of Technology, Department of Physics , Armii Krajowej 19 Av., 42-200 Częstochowa
  3. Electro Sistem, 4B, 8 Martie Street, 430406, Baia Mare, Maramures, Romania
  4. ”Lucian Blaga” University of Sibiu, Faculty of Engineering, Industrial Engineering and Management Department , 10 Victoriei Street, 550024, Sibiu, Romania

Abstrakt

Wybitny współczesny artysta libański, Akram Zaatari, ukazuje skomplikowaną powojenną sytuację wielokulturowego społeczeństwa Bliskiego Wschodu w kontekście dawnego Imperium Osmańskiego. Swoją konceptualną praktykę artystyczną przyrównuje do pracy archeologa na wykopaliskach. Jako artysta-archiwista przywołuje europejski humanizm w heroicznej wersji egzystencjalizmu.
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Autorzy i Afiliacje

Zofia Chojnacka
1
ORCID: ORCID

  1. Instytut Sztuki PAN
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Abstrakt

This work attempts to use nitrogen gas as a shielding gas at the cutting zone, as well as for cooling purposes while machining stainless steel 304 (SS304) grade by Computer Numerical Control (CNC) lathe. The major influencing parameters of speed, feed and depth of cut were selected for experimentation with three levels each. Totally 27 experiments were conducted for dry cutting and N2 gaseous conditions. The major influencing parameters are optimized using Taguchi and Firefly Algorithm (FA). The improvement in obtaining better surface roughness and Material Removal Rate (MRR) is significant and the confirmation results revealed that the deviation of the experimental results from the empirical model is found to be within 5%. A significant improvement of reduction of the specific cutting energy by 2.57 % on average was achieved due to the reduction of friction at the cutting zone by nitrogen gas in CNC turning of SS 304 alloy.

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Bibliografia

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  14.  J. Rajaparthiban and A.N. Sait, “Application of the grey-based Taguchi method and Deform-3D for optimizing multiple responses in turning of Inconel 718”, Mater. Test. 60(9), 907‒912 (2018).
  15.  T. Kıvak and Ş. Mert, “Application of the Taguchi technique for the optimization of surface roughness and tool life during the milling of Hastelloy C22”, Mater. Test. 59(1), 69‒76 (2017).
  16.  R.N. Yadav, “A Hybrid Approach of Taguchi-Response Surface Methodology for Modeling and Optimization of Duplex Turning Process”, Measurement 100, 131‒138 (2016).
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  18.  P. Raja, R. Malayalamurthi, and M. Sakthivel, “Experimental investigation of cryogenically treated HSS tool in turning on AISI1045 using fuzzy logic – Taguchi approach”, Bull. Pol Ac.: Tech. 67(4),687‒696 (2019).
  19.  G.V. Chakaravarthy, S. Marimuthu, and A. Naveen Sait, “Comparison of Firefly algorithm and Artificial Immune System algorithm for lot streaming in m-machine flow shop scheduling”, Int. J. Comput. Intell. Syst. 5(6), 1184‒1199 (2012).
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  23.  N.A. Al-Thanoon, O.S. Qasim, and Z.Y. Algamal, “A new hybrid firefly algorithm and particle swarm optimization for tuning parameter estimation in penalized support vector machine with application in chemometrics”, Chemometrics Intell. Lab. Syst. 184, 142‒152 (2019).
  24.  A.F. Zubair, M. Salman, and A. Mansor, “Embedding firefly algorithm in optimization of CAPP turning machining parameters for cutting tool selections”, Comput. Ind. Eng. 135, 317‒325 (2019).
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Autorzy i Afiliacje

P. Prasanth
1
T. Sekar
2
M. Sivapragash
3

  1. Department of Mechanical Engineering, Tagore Institute of Engineering and Technology, Deviyakurichi, Salem – 636112, Tamilnadu, India
  2. Department of Mechanical Engineering, Government College of Technology, Coimbatore – 641013, Tamilnadu, India
  3. Department of Mechanical Engineering, Universal College of Engineering and Technology, Vallioor, Tirunelveli – 627117, Tamilnadu, India

Abstrakt

The current passed by the stator coil of the permanent magnet synchronous motor (PMSM) provides rotating magnetic field, and the number of turns will directly affect the performance of PMSM. In order to analyze its influence on the PMSM performance, a 3 kW, 1500 r/min PMSM is taken as an example, and the 2D transient electromagnetic field model is established. The correctness of the model is verified by comparing the experimental data and calculated data. Firstly, the finite element method (FEM) is used to calculate the electromagnetic field of the PMSM. The performance parameters of the PMSM are obtained. On this basis, the influence of the number of turns on PMSM performance is quantitatively analyzed, including current, no-load back electromotive force (EMF), overload capacity and torque. In addition, the influence of the number of turns on eddy current loss is further studied, and its variation rule is obtained, and the variation mechanism of eddy current loss is revealed. Finally, the temperature field of the PMSM is analyzed by the coupling method of electromagnetic field and temperature field, and the temperature rise law of PMSM is obtained. The analysis of this paper provides reference and practical value for the optimization design of PMSM.

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Autorzy i Afiliacje

H. Qiu
Y. Zhang
C. Yang
R. Yi

Abstrakt

The dynamic development of science requires constant improvement of approaches to modeling physical processes and phenomena. Practically all scientific problems can be described by systems of differential equations. Many scientific problems are described by systems of differential equations of a special class, which belong to the group of so-called singularly perturbed differential equations. Mathematical models of processes described by such differential equations contain a small parameter near the highest derivatives, and it was the presence of this small factor that led to the creation of a large mathematical theory. The work proposes a developed algorithm for constructing uniform asymptotics of solutions to systems of singularly perturbed differential equations.
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Autorzy i Afiliacje

Valentyn Sobchuk
1
ORCID: ORCID
Iryna Zelenska
1
ORCID: ORCID
Oleksandr Laptiev
1
ORCID: ORCID

  1. Taras Shevchenko National University of Kyiv, Ukraine

Abstrakt

In the extensive polemic with the book Haunting History: For a Deconstructive Approach to the Past by Ethan Kleinberg, the reviewer comments on the innovative potential of deconstruction as it enables the conception of various scenarios of the future. Kleinberg’s reflections on the ontology (or hauntology) of the past are located within the current discussion about “the ontological turn.” The reviewer compares Kleinberg’s take on a deconstructive approach to the past with similar considerations presented by Sande Cohen in the US as well as by Keith Jenkins, Alun Munslow and, more recently, Berber Bevernage in Europe.

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Autorzy i Afiliacje

Ewa Domańska
ORCID: ORCID

Abstrakt

This paper presents a study on the dry turning of polyoxymethylene copolymer POM-C. The effect of five factors (cutting speed, feed rate, depth of cut, nose radius, and main cutting edge angle) on machinability is evaluated using four output parameters: surface roughness, tangential force, cutting power, and material removal rate. To do so, the study relies on three approaches: (i) Pareto statistical analysis, (ii) multiple linear regression modeling, and (iii) optimization using the genetic algorithm. To conduct the investigation, mathematical models are developed using response surface methodology based on the Taguchi L16 orthogonal array. The results indicate that feed rate, nose radius, and cutting edge angle significantly influence surface quality, while depth of cut, feed, and speed have a notable impact on other machinability parameters. The developed mathematical models have determination coefficients greater than or very close to 95%, making them very useful for the industry as they allow predicting response values based on the chosen cutting parameters. Finally, the optimization using the genetic algorithm proves to be promising and effective in determining the optimal cutting parameters to maximize productivity while improving surface quality.
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Autorzy i Afiliacje

Tallal Hakmi
ORCID: ORCID
Amine Hamdi
ORCID: ORCID
Youssef Touggui
ORCID: ORCID
Aissa Laouissi
ORCID: ORCID
Salim Belhadi
ORCID: ORCID
Mohamed Athmane Yallese
ORCID: ORCID

Abstrakt

This article discusses some proposals aimed at creating a new discipline named polonistyka (Polish studies), an umbrella term which would encompass those research (sub)divisions that fall outside the traditional academic taxonomy. The article identifies three cultural turns whose shockwave effect have significantly changed the face of the humanities. They are the transition from the analogue to the digital; an impasse in the interdisciplinary and transdisciplinary studies; and the continual fragmentation of research interests. The new discipline, as envisaged by the article, would reintegrate and provide institutional recognition to all kinds of studies, projects and probes. It would also create a framework for some kind of academic certification of research interests that are in dispute. To achieve these goals it would be necessary to redefine the subject matter, the scope as well as the functioning of the new discipline. That, in turn, implies a reformatting of the legacy model of teaching and study to fit in with the new discipline. The transition is absolutely necessary, not least because of the real danger of marginalization and pauperization of the profession (i.e. teachers and specialists in the field of ‘Polish philology’).
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Autorzy i Afiliacje

Ryszard Nycz
1
ORCID: ORCID

  1. Uniwersytet Jagielloński

Abstrakt

W artykule przedstawia się spór o charakter deskrypcji określonych, który miał miejsce na łamach czasopisma „Mind” między Peterem Strawsonem a Bertrandem Russellem. Spór ten wykracza poza próbę uzasadnienia odmiennych rozstrzygnięć pewnych problemów związanym z użyciem deskrypcji, gdyż odwołuje się do dwóch odmiennych tradycji w ramach filozofii analitycznej, które można nazwać filozofią języka naturalnego oraz filozofią języka idealnego. Celem artykułu jest zarysowanie głównych cech owych tradycji oraz wskazanie, w jaki sposób rzutowały one na ową polemikę. W pierwszym paragrafie omawiam teorię deskrypcji Russella na tle przemian jego poglądów filozoficznych, które następowały od końca XIX wieku do opublikowania w roku 1905 słynnego artykułu On Denoting. Drugi paragraf poświęcam krótkiemu omówieniu wspomnianych tradycji oraz roli Strawsona w filozofii języka naturalnego. W kolejnym paragrafie analizuję zarzuty Strawsona wobec teorii deskrypcji, skupiając się niekiedy na detalach, które są zazwyczaj pomijane w standardowych prezentacjach. Ostatni paragraf poświęcony jest odpowiedzi Russella na zarzuty Strawsona. Kontrargumenty Russella omawiam w kontekście reprezentowanej przez niego filozofii języka idealnego i sugeruję, w jaki sposób można niekiedy pogodzić oba podejścia.

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Autorzy i Afiliacje

Janusz Maciaszek
ORCID: ORCID

Abstrakt

The popularity of high-efficiency permanent magnet synchronous motors in drive systems has continued to grow in recent years. Therefore, also the detection of their faults is becoming a very important issue. The most common fault of this type of motor is the stator winding fault. Due to the destructive character of this failure, it is necessary to use fault diagnostic methods that facilitate damage detection in its early stages. This paper presents the effectiveness of spectral and bispectrum analysis application for the detection of stator winding faults in permanent magnet synchronous motors. The analyzed diagnostic signals are stator phase current, stator phase current envelope, and stator phase current space vector module. The proposed solution is experimentally verified during various motor operating conditions. The object of the experimental verification was a 2.5 kW permanent magnet synchronous motor, the construction of which was specially prepared to facilitate inter-turn short circuits modelling. The application of bispectrum analysis discussed so far in the literature has been limited to vibration signals and detecting mechanical damages. There are no papers in the field of motor diagnostic dealing with the bispectrum analysis for stator winding fault detection, especially based on stator phase current signal.
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Autorzy i Afiliacje

Przemysław Pietrzak
1
ORCID: ORCID
Marcin Wolkiewicz
1
ORCID: ORCID

  1. Wrocław University of Science and Technology, Department of Electrical Machines, Drives and Measurements, Wybrzeze Wyspia ˙ nskiego 27, ´ 50-370 Wrocław, Poland

Abstrakt

In the current paper, the effect of tool wear for a constant period of time (360 s) during conventional and ultrasonic assisted machining of Inconel 718 is investigated in terms of cutting forces, temperature, and deviation measurements. For fixed process parameters turning experiments have been performed with and without the application of tangential vibration. Ultrasonic assisted turning (UAT) experiments have been compared with conventional turning (CT). The experimental results reveal that cutting forces and temperature increase linearly in the case of UAT whereas remaining constant in CT for a constant period of time. Besides the tool wear rate in the case of UAT is more than that in the CT.
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Autorzy i Afiliacje

Srihari Dodla
1
ORCID: ORCID

  1. Department of Mechanical Engineering, Indian Institute of Technology (BHU), Varanasi-221005, India

Abstrakt

Ludowa historia Polski. Historia wyzysku i oporu. Mitologia panowania (A People's History of Poland. A history of exploitation and resistance. The mythology of reign) (2020) by Adam Leszc-zyński, met with great interest, both in the academic community and wider reading circles. Re-viewed many times, it was the subject of discussion in scientific periodicals, opinion‑forming press, and on the Internet. In this article, based on published and shared online reviews, debates, discus-sions, etc., I will consider the reasons for the social resonance of the book. I will look at how it was received by members of the Academy (primarily historians and sociologists). Was Did the “new” approach to folk history proposed by Leszczyński meet with their acceptance? How did they evaluate the manner and degree of achievement of the goals set by the author? I will also be interested in assessments of methodological competences, scientific workshop technique and opi-nions on the benefits that science (mainly the humanities) has gained thanks to the author's findings.
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Autorzy i Afiliacje

Jolanta Kolbuszewska
1
ORCID: ORCID

  1. Instytut Historii UŁ

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