Relevant bibliographies by topics / Rotational hysteresis

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  1. Journal articles
  2. Dissertations / Theses
  3. Book chapters
  4. Conference papers

Academic literature on the topic 'Rotational hysteresis'

Author: Grafiati
Published: 4 June 2021
Last updated: 1 February 2022

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Journal articles on the topic "Rotational hysteresis"

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Elk, K. "Rotational Hysteresis Work and Rotational Hysteresis Integral of Polycrystalline Permanent Magnets." physica status solidi (b) 182, no. 2 (April 1, 1994): 453–60. http://dx.doi.org/10.1002/pssb.2221820223.

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Elk, K., and V. Christoph. "Hysteresis and rotational hysteresis of textured polycrystalline magnets." Journal of Magnetism and Magnetic Materials 65, no. 1 (February 1987): 151–58. http://dx.doi.org/10.1016/0304-8853(87)90320-9.

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Keller, R., and E. Schmidbauer. "Magnetic hysteresis properties and rotational hysteresis losses of synthetic stress-controlled titanomagnetite (Fe2.4Ti0.6O4) particles-II. Rotational hysteresis losses." Geophysical Journal International 138, no. 2 (August 1999): 334–42. http://dx.doi.org/10.1046/j.1365-246x.1999.00853.x.

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Harrison, S. A., R. Street, J. R. Budge, and S. K. Jones. "Rotational hysteresis losses in isotropic media." IEEE Transactions on Magnetics 35, no. 5 (1999): 3962–64. http://dx.doi.org/10.1109/20.800722.

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Jiang, J. S., S. D. Bader, H. Kaper, G. K. Leaf, R. D. Shull, A. J. Shapiro, V. S. Gornakov, et al. "Rotational hysteresis of exchange-spring magnets." Journal of Physics D: Applied Physics 35, no. 19 (September 13, 2002): 2339–43. http://dx.doi.org/10.1088/0022-3727/35/19/303.

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Elk, K. "Rotational hysteresis of polycrystalline permanent magnets." Journal of Magnetism and Magnetic Materials 123, no. 1-2 (May 1993): 117–25. http://dx.doi.org/10.1016/0304-8853(93)90020-3.

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Muxworthy, A. R. "Magnetic hysteresis and rotational hysteresis properties of hydrothermally grown multidomain magnetite." Geophysical Journal International 149, no. 3 (May 26, 2002): 805–14. http://dx.doi.org/10.1046/j.1365-246x.2002.01685.x.

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VAN DRENT, William, Eelco STERRINGA, Cock LODDER, Giancarlo BOTTONI, D. CANDOLFO, A. CECCHETTI, and F. MASOLI. "ROTATIONAL HYSTERESIS MEASUREMENTS ON ALUMITE PERPENDICULAR MEDIA." Journal of the Magnetics Society of Japan 15, S_2_PMRC_91 (1991): S2_951–957. http://dx.doi.org/10.3379/jmsjmag.15.s2_951.

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Louail, L., F. Djabou, D. Maouche, and H. Hachemi. "Rotational hysteresis energy in Co/Tb multilayers." Materials Chemistry and Physics 82, no. 1 (September 2003): 145–50. http://dx.doi.org/10.1016/s0254-0584(03)00202-5.

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Callegaro, L., and E. Puppin. "Rotational hysteresis model for stressed ferromagnetic films." IEEE Transactions on Magnetics 33, no. 2 (1997): 1007–11. http://dx.doi.org/10.1109/20.558520.

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Dissertations / Theses on the topic "Rotational hysteresis"

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Harrison, Simon Andrew. "Characterisation of the mechanisms of magnetisation change in permanent magnet materials through the interpretation of hysteresis measurements." University of Western Australia. School of Physics, 2004. http://theses.library.uwa.edu.au/adt-WU2004.0048.

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The mechanisms by which magnetisation changes occur in magnetic materials may be investigated by a variety of hysteresis measurements. During this study both alternating and rotational hysteresis measurements were used to characterise the mechanisms of magnetisation change in a number of permanent magnet materials. Studies of the time dependence of magnetisation, remanent magnetisations and the dependence of the reversible magnetisation on the irreversible magnetisation were undertaken. These studies revealed that in sintered rare-earth iron magnets the magnetisation change is predominately controlled by domain nucleation, with a lesser contribution from domain wall pinning within the boundary regions of the grains. Similar mechanisms control the magnetisation change in the larger grains of melt-quenched rare-earth iron magnets. In the single domain grains of the melt-quenched materials incoherent rotation mechanisms control the changes of magnetisation. Magnetisation change in MnAlC and sintered AlNiCo was found to be controlled by domain wall pinning within the interior of the grains of the materials. Two devices were constructed for the measurement of rotational hysteresis. The first measures the angular acceleration of a sample set spinning in a magnetic field, from which the rotational hysteresis loss may be determined. The second employs rotating search coils to make direct measurements of the component of magnetisation that contributes to rotational hysteresis loss during the rotation of a sample in a field. Both devices were found to produce data consistent with that in the literature and to be useful for the characterisation of rotational hysteresis in permanent magnet materials. A simple model was used to examine the dependence of rotational hysteresis loss on various material parameters. It was found that the value of the rotational hysteresis integral is dependent on interactions and to a lesser extent distributions in anisotropy. This is contrary to assumptions commonly made in the literature but consistent with published experimental data, which has been reinterpreted. Measurements of rotational hysteresis losses in the materials studied were found to be effected by geometric demagnetisation effects. A method by which such data may be corrected for these effects is proposed. Following correction and consideration of the interactions within the materials, the rotational hysteresis data was found to be consistent with the characterisations performed in linearly alternating fields.
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Rigue, Josué Neroti. "Estudo da anisotropia unidirecional e da histerese rotacional em sistemas com exchange bias." Universidade Federal de Santa Maria, 2014. http://repositorio.ufsm.br/handle/1/3924.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
The exchange bias (EB) phenomen occurs due to the coupling between ferromagnetic and antiferromagnetic material and the main characteristics are the rise of unidirectional anisotropy and the rotational hysteresis in torque curves. In this work we have investigated how the unidirectional anisotropy and the rotational hysteresis are influenced by the change of some characteristics in thin films samples. Among these are the stacking of layers, the roughness at the interface between the two materials, the difference in the ferromagnetic layer thickness and the difference between the antiferromagnetic materials. The study was made by using magnetic torque measurements which were interpreted using a granular model for the EB. The parameters obtained from the fitting of the model to the torque curves has also permitted to reproduce data obtained by different magnetic techniques, especially in samples where the unidirectional anisotropy is greater than the uniaxial anisotropy. In NiFe=IrMn samples, the unidirectional anisotropy is favored by stacking layers, by increasing of the interfacial roughness and by the decrease of the ferromagnetic layer thickness, while the rotational hysteresis is substantially increased as the interfacial roughness increases. For the NiFe=FeMn sample the highest values of unidirectional anisotropy and rotational hysteresis were found, as well as a dependence of these parameters with the measuring magnetic field.
O fenômeno de "exchange bias" (EB) ocorre quando um material ferromagnético está acoplado a um material antiferromagnético e apresenta como características principais o surgimento de uma anisotropia unidirecional e a histerese rotacional em curvas de torque. Nesse trabalho foi investigado como a anisotropia unidirecional e a histerese rotacional são influenciadas pela mudança de algumas características em amostras na forma de filme finos. Entre essas características estão o empilhamento de camadas, a rugosidade na interface entre os dois materiais, a diferença na espessura da camada ferromagnética e a diferença entre os materiais antiferromagnéticos. O estudo foi realizado através de medidas de magnetometria de torque nas amostras, as quais foram interpretadas usando um modelo granular para o EB. Os parâmetros resultantes do ajuste do modelo às curvas de torque permitiram também reproduzir dados obtidos por outras técnicas de caracterização magnética, sobretudo em amostras que apresentam a anisotropia unidirecional maior do que a anisotropia uniaxial. Em amostras de NiFe=IrMn, a predominância da anisotropia unidirecional é favorecida pelo empilhamento de camadas, pelo aumento da rugosidade interfacial e pela diminuição da espessura da camada ferromagnética, enquanto a histerese rotacional apresenta aumento significativo somente com o aumento da rugosidade. Em uma amostra de NiFe=FeMn foram encontrados valores maiores tanto para a anisotropia unidirecional quanto para a histerese rotacional, bem como uma dependência desses com o campo de medida.
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Silva, Oreci Escobar da. "Estudo do exchange bias em filmes finos de NiFe/FeMn (bicamadas) E NiFe/IrMn (multicamadas)." Universidade Federal de Santa Maria, 2016. http://repositorio.ufsm.br/handle/1/9257.

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Fundação de Amparo a Pesquisa no Estado do Rio Grande do Sul
The Exchange Bias (EB) phenomenon consists of an interfacial exchange coupling between a ferromagnetic (FM) material and an antiferromagnetic (AFM) one and has as the main characteristics the rise of a unidirectional anisotropy and a rotational hysteresis (HR) in torque curves. In this work we have investigated the behavior of the magnetic behavior of systems presenting EB through magnetization curves, anisotropic magnetorresistance (AMR)and torque magnetometry. We have grown films, via magnetron sputtering, of NiFe/FeMn (bilayers) with different thickness of the FM layer and film structures of NiFe/IrMn/Ta with different repetitions of the basic s tructure. From the X-ray diffraction and reflectivity we have determined the preferential crystallographic growth direction, the thickness and the grain size of the studied samples. It was implemented at the Magnetism and Magnetic Materials Laboratory (LMMM) an apparatus to measure the AMR in two configurations: resistance as a function of the applied field angle and resistance as function of the field applied in a particular angle direction. To adjust the magnetization and AMR data we have used a phenomenological model for EB considering four energy terms: Zeeman, uniaxial, unidirectional and magnetostatic. The AMR curves have shown an asymmetry around 180º when measured at field smaller than the Bias one. According to the used model used, such asymmetry can be caused either by a misalignment between the anisotropy axes (uniaxial and unidirectional) or by a misalignment between the measurement current direction easy magnetization axis of the sample. It was not observed in the multilayers an increase on the uniaxial anisotropy dispersion with increasing on the trilayers number, as expected. In order to fit average torque curves, we have used an equation with two harmonic terms. The resulting parameters allow us to study the field evolution of the harmonic amplitudes Kθ e K2θ. In the multilayer system as higher total energy is, higher is the energy losses by HR. In bilayers system, the HR energy losses still increases even above the saturation field. Such behavior was associated to the configuration of interfacial spins and suggests the need of an additional contribution to total energy of the magnetic system.
O fenômeno de Exchange Bias (EB) consiste de um acoplamento de troca interfacial entre um material ferromagnético (FM) e um material antiferromagnético (AFM) e tem como características principais o surgimento de uma anisotropia unidirecional e a histerese rotacional (HR) em curvas de torque. Neste trabalho investigamos o comportamento de sistemas magnéticos com EB através de curvas de magnetização, magnetorresistência anisotrópica (AMR) e magnetometria de torque. Foram crescidos filmes via magnetron sputtering, de NiFe/FeMn (bicamadas) variando a espessura da camada de NiFe e filmes de NiFe/IrMn/Ta com diferentes números de repetições dessa estrutura básica (multicamadas). A partir da difração e refletividade de raios-X determinamos a direção preferencial de crescimento cristalográfico, espessura e o tamanho de grão das amostras estudadas. Foi implementado no Laboratório de Magnetismo e Materiais Magnéticos (LMMM) um aparato experimental para medidas de AMR: resistência em função do ângulo do campo aplicado e resistência em função do campo aplicado para um determinado ângulo escolhido. Para o ajuste aos dados das curvas de magnetização e AMR é apresentado um modelo fenomenológico para EB considerando quatro termos de energia: Zeeman, uniaxial, unidirecional e magnetostático. As curvas de AMR apresentam uma assimetria em torno de 180º quando medidas em valores de campo menores que o campo de Bias. De acordo com o modelo utilizado, tal assimetria pode ser causada por um desalinhamento entre os eixos de anisotropia (uniaxial e unidirecional) ou por um desalinhamento entre a direção da corrente de medida e o eixo fácil de magnetização da amostra. Não foi observado um aumento na dispersão da anisotropia uniaxial com o aumento das repetições das tricamadas, conforme esperado. Para o ajuste das curvas de torque médio utilizamos uma equação com dois termos harmônicos. Os parâmetros resultantes do ajuste das curvas de torque permitiram estudar a evolução das componentes harmônicas Kθ e K2θ. Nas multicamadas quanto maior a energia associada ao torque médio maiores são as perdas de energia por HR. Já nas bicamadas, as perdas de energia por HR aumentam mesmo acima do campo de saturação. Tal comportamento foi associado à configuração de spins interfaciais e sugere a necessidade de uma contribuição adicional para a energia total do sistema magnético.
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Dogantimur, Erkan, and Daniel Johnsson. "Analysis of Accuracy for Engine and Gearbox Sensors." Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-388346.

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This thesis provides a standardized method to measure accuracy for engine and gearbox sensors. Accuracy is defined by ISO 5725, which states that trueness and precision need to be known to provide a metric for accuracy. However, obtaining and processing the data required for this is not straight forward. In this thesis, a method is presented that consists of two main parts: data acquisition and data analysis. The data acquisition part shows how to connect all of the equipment used and how to sample and store all the raw data from the sensors. The data analysis part shows how to process that raw data into statistical data, such as trueness, repeatability and reproducibility for the sensors. Once repeatability and reproducibility are known, the total precision can be determined. Accuracy can then be obtained by using information from trueness and precision. Besides, this thesis shows that measurement error can be separated into error caused by the sensors and error caused by the measurand. This is useful information, because it can be used to assess which type of error is the greatest, whether or not it can be compensated for, and if it is economically viable to compensate for such error.  The results are then shown, where it is possible to gain information about the sensors’ performance from various graphs. Between Hall and inductive sensors, there were no superior winner, since they both have their strengths and weaknesses. The thesis ends by making recommendations on how to compensate for some of the errors, and how to improve upon the method to make it more automatic in the future.
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Tchangoulian, Ardaches. "Utilisation de matériaux composites magnétiques à nanoparticules pour la réalisation de composants passifs non réciproques micro-ondes." Thesis, Saint-Etienne, 2014. http://www.theses.fr/2014STET4016/document.

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Dans les systèmes des télécommunications, beaucoup d’études ont été entreprises pour intégrer des composants passifs non réciproques. Le bon fonctionnement des circulateurs exige souvent des aimants volumineux et lourds qui assurent une orientation uniforme des moments magnétiques du matériau ferrite. Pour tendre vers l’intégration et la miniaturisation des circulateurs, les nanotechnologies peuvent offrir des solutions intéressantes. L’objectif de cette thèse a été de développer un circulateur coplanaire auto-polarisé. L'approche choisie est fondée sur la réalisation de substrats composites à «nano-fil ferrimagnétiques». Elle consiste à faire un dépôt par magnétophorèse ou dip-coating de nanoparticules de ferrite de cobalt dans des membranes d’alumine poreuses et de les orienter sous champ magnétique de manière uniforme. Des substrats composites magnétiques ont été fabriqués à partir de nanoparticules CoFe2O4 dispersées dans une matrice sol-gel de silice en utilisant la technique de Dip-coating avec et sans un champ magnétique appliqué. De nombreuses études ont été faites afin d'étudier le comportement magnétique et diélectrique de ces substrats : VSM, polarimétrie spectrale, MFM et autres. Les cycles d'hystérésis montrent une forte différence des valeurs des champs coercitifs (μ0Hc) et rémanents (Mr/Ms) si, durant la fabrication, un champ magnétique est appliqué ou non, démontrant ainsi l'orientation (ou non) des nanoparticules. Ce nano-composite est un candidat intéressant pour la fabrication de circulateurs même si la concentration et l’orientation des particules sont insuffisantes. Des circulateurs ont été conçus, modélisés et simulés à l'aide du logiciel HFSS. Suite à des résultats de simulation intéressants; un premier prototype a été fabriqué et caractérisé en hautes fréquences. Les résultats de mesure ont montré un phénomène de circulation, qui reste très faible en raison du faible pourcentage de nanoparticules magnétiques dans le composite et de leur orientation imparfaite. Les verrous technologiques ont été clairement identifiés et ne permettent pas, pour l’instant, de réaliser un circulateur opérationnel
In telecommunications systems, many studies have been undertaken to integrate non-reciprocal passive components. The proper functioning of circulators often requires large and heavy magnets that ensure a uniform orientation of the magnetic moments of the ferrite material. To work towards the integration and miniaturization of circulators, nanotechnology can offer interesting solutions. The aim of this thesis was to develop a self-biased coplanar circulator. The approach is based on the production of composite substrates "ferrimagnetic nanowire." It consists in a magnetophoresis or a dip-coating deposition of cobalt ferrite nanoparticles in porous alumina membranes and orienting them in a magnetic field uniformly. Magnetic composite substrates were made from CoFe2O4 nanoparticles dispersed in a matrix of silica sol-gel using the dip-coating technique with and without an applied magnetic field. Many studies have been made to study the magnetic and dielectric behavior of these substrates: VSM, spectral polarimetry, MFM and others. The hysteresis loops show a strong difference in the values of coercive fields (μ0Hc) and persistent (Mr / Ms) if, during the fabrication, a magnetic field is applied or not, therefore showing the orientation (or not) of nanoparticles. This nano-composite is an interesting candidate for the fabrication of circulators even if the concentration and the particle orientation are insufficient. Circulators were designed, modeled and simulated using the HFSS software. Following the interesting results of simulation; a first prototype was fabricated and characterized at high frequencies. The measurement results showed a circulation phenomenon, which is very low due to the small percentage of magnetic nanoparticles in the composite and their imperfect orientation. Technological barriers have been clearly identified and do not allow for the time to achieve an operational circulator
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Acun, Bora. "Energy Based Seismic Performance Assessment Of Reinforced Concrete Columns." Phd thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12611728/index.pdf.

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Severe seismic events in urban regions during the last two decades revealed that the structures constructed before the development of modern seismic codes are the most vulnerable to earthquakes. Sub-standard reinforced concrete buildings constitute an important part of this highly vulnerable urban building stock. There is urgent need for the development and improvement of methods for seismic performance assessment of existing reinforced concrete structures. As an alternative to current conventional force-based assessment methods, a performance evaluation procedure for structural members, mainly reinforced concrete columns is proposed in this study, by using an energy-based approach combined with the low cycle fatigue concept. An energy-based hysteresis model is further introduced for representing the inelastic response of column members under severe seismic excitations. The shape of the hysteresis loops are controlled by the dissipated cumulative energy whereas the ultimate strength is governed by the low cycle fatigue behavior. These two basic characteristics are obtained experimentally from full scale specimens tested under constant and variable amplitude displacement cycles. The first phase of the experimental program presented in the study constitutes of testing sub-standard non-conforming column specimens. The second phase of testing was conducted on standard, code compliant reinforced concrete columns. A total number of 13 specimens were tested. The behavior of these specimens was observed individually and comparatively according to the performance based objectives. The results obtained from the experiments were employed for developing relations between the energy dissipation capacity of specimens, the specimen properties as well as the imposed displacement history. Moreover, the measured rotation capacities at the plastic regions are evaluated comparatively with the limits proposed by modern displacement-based seismic design and assessment provisions.
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Lu, Chi-Lang, and 陸琪朗. "Rotational hysteresis in single domain ferromagnetic particle." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/46321722174560011444.

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碩士
國立中山大學
物理學系研究所
88
A ferromagnetic particle with single domain, at some kinds of applied field (at some angle or strangth), the particle's free energy would be two state model. The rate of barrier crossing could be solve by Fokker-Planck equation .And use master equation to find out the Total rate between two potential well. In this thysis, we use the upper method to simulate particle's magnetic moment under time varying magnetic field at fixed angle or fixed magnetic applied rotate the particle. In numerical method, we use the back Euler method to prevent the divergence of the calculation.
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Κόντος, Αναστάσιος. "Υπολογισμός απωλειών ασύγχρονης μηχανής τροφοδοτούμενης μέσω αντιστροφέα τάσης ελεγχόμενου με τεχνική PWM." Thesis, 2012. http://hdl.handle.net/10889/5593.

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Στις ηλεκτρικές μηχανές ο υπολογισμός των απωλειών και οι μηχανισμοί που τις προκαλούν αποτελούν ένα πολύ απαιτητικό αντικείμενο μελέτης. Τα τελευταία χρόνια καθώς αυξάνεται η ανάγκη για ολοένα και πιο αποδοτικές μηχανές μεγάλο κομμάτι της έρευνας έχει επικεντρωθεί στον υπολογισμό των απωλειών τους και πιο συγκεκριμένα στον υπολογισμό των απωλειών σιδήρου. Οι απώλειες σιδήρου ή αλλιώς απώλειες πυρήνα αποτελούν σημαντικό μέρος των απωλειών μια μηχανής, ταυτόχρονα όμως ο υπολογισμός τους εμφανίζει ιδιαίτερη δυσκολία. Στην παρόυσα διπλωματική εργασία η προσπάθεια επικεντρωνεται στον υπολογισμό αυτών των απωλειών σε μια ασύγχρονη μηχανή με διάφορες μεθόδους. Πιο συγκεκριμένα, στο πρώτο κεφάλαιο γίνεται μια εισαγωγή στα σιδηρομαγνητικά υλικά και στις ιδιότητες τους. Αρχικά παρουσιάζεται το φαινόμενο της μαγνήτισης και του κορεσμού. Στη συνέχεια μελετάται το φαινόμενο της υστέρησης και οι ιδιότητες της που παίζουν καθοριστικό ρόλο στις απώλειες του πυρήνα της μηχανής, αλλά και το φαινόμενο των δινορευμάτων. Στο δεύτερο κεφάλαιο μελετώνται οι απώλειες της μηχανής. Με ποιό τρόπο δηλαδή το φαινόμενο της υστέρησης και των δινορευμάτων πρoκαλούν απώλειες στη μηχανή και με ποια μορφή εμφανίζονται. Παρουσιάζονται ακόμα οι μηχανισμοί που συνδέονται με τις απώλειες χαλκού, επιδερμικό φαινόμενο και φαινόμενο γειτνίασης και ο ρόλος τους. Παρουσιάζεται επίσης μια βιβλιογραφική έρευνα σχετικά με τις διάφορες μεθόδους που χρησιμοποιούνται για τον υπολογισμό των απωλειών σιδήρου. Το τρίτο κεφάλαιο αποτελεί ουσιαστικά μια εισαγωγή στα ηλεκτρονικά ισχύος και πιο συγκεκριμένα στον αντιστροφέα τάσης με τεχνική PWM. Σημαντικός θεωρείται ο τρόπος με τον οποίο διαμορφώνεται η τάση εισόδου στη μηχανή, αλλά και η μορφή της, καθώς επηρεάζει άμεσα τις απώλειες σιδήρου της μηχανής. Στο τέταρτο και τελευταίο κεφάλαιο βρίσκουν εφαρμογή όλα τα παραπάνω. Η εργασία γίνεται με τη βοήθεια ενός μοντέλου πεπερασμένων στοιχείων, δύο διαστάσεων, μιας ασύγχρονης μηχανής βραχυκυκλωμένου κλωβού. Αρχικά η μηχανή τροφοδοτείται από μια ημιτονοειδή τάση είσόδου. Υπολογίζονται οι απώλειες χαλκού και στη συνέχεια οι απώλειες σιδήρου με τη βοήθεια υπολογιστικών μεθόδων ανάλυσης του μαγνητικού πεδίου σε σειρές Fourier. Τέλος μελετάται η μορφή του μαγνητικού πεδίου σε διάφορα σημεία της μηχανής και οι απώλειες που εμφανίζεται σε κάθε στοιχείο του μοντέλου ανά περίπτωση. Τα βήματα αυτά επαναλαμβανονται τροφοδοτώντας αυτή τη φορά τη μηχανή μέσω αντιστροφέα τάσης με τεχνική PWM. Συγκρίνοντας τα αποτελέσματα από κάθε περίπτωση εξάγονται σημαντικά συμπεράσματα για τις απώλειες της μηχανής και τη συμπεριφορά των μηχανισμών που τις προκαλούν.
In electrical machines the calculation of loss and the mechanisms that cause them are a very demanding subject of study. Recently, the increasing need for ever more efficient machines has made the research focus on the calculation of their losses and more specifically the calculation of the iron losses. The iron losses or core losses, constitute an important part of the total machine losses, but also their calculation is particularly difficult. In this thesis we focus on the calculation of these losses in an asynchronous machine using various methods. More specifically, the first chapter is an introduction to the properties of ferromagnetic materials. First, we study the phenomenon of magnetization and saturation and then we examine the phenomenon of hysteresis and its properties which play a crucial role in the core losses of the machine. Finally we study eddy current phenomenon. In the second chapter we discuss the losses of the machine. In which way the phenomenon of hysteresis and eddy currents generate losses in the machine and the form in which they appear. Also presented are the mechanisms associated with the copper losses, skin effect and proximity effect. Also shown is a literature survey on various methods used to calculate the iron losses. The third chapter is essentially an introduction to power electronics, and more particularly to the PWM technique. Important in this chapter is the way in which the input voltage to the machine affects the iron losses. In the fourth and final chapter we produce results of the above theory using simulation methods. The work is done using a finite element model in two dimensions of a squirrel cage asynchronous machine. Initially the machine is fed by a sinusoidal input voltage. Firstly copper losses are calculated and then the iron losses with the help of computational methods which analyze the magnetic induction in Fourier series. Finally, we study the shape of the magnetic field in different parts of the machine and the losses occurring in each element of the model in each case. These additional losses are known as rotational core losses. These steps are repeated, this time powering the machine via inverter supply using the PWM technique.
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Fan, Chiang, and 范強. "Effect of Dipole Rotation on Hysteresis in Methylammonium Lead Bromide." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/86968g.

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碩士
國立臺灣大學
應用物理研究所
107
Electric-field-induced dipole rotation of the intercalated organic molecules in halide perovskites has been suggested to be one controllable factor for fundamental properties and stabilities in perovskites. However, up to now, how the electric field triggers the dipole rotation of the intercalated organic molecules is still unknown. Here, we record the real-space atomic image and simultaneously probe the corresponding current-voltage (I-V) hysteresis in the methylammonium lead bromide (MAPbBr3) system using cross-sectional scanning tunneling microscopy and spectroscopy. In this work, we addressed the change of topography at specific bias intervals and anomalous I-V hysteresis with four gap-like regions as well as two unusual inflection points at forward 1.68 V and backward -0.87 V under ramp reversal scanning mode. We suppose that the dipole rotation, initiated by an electric field, concludes to two opposite surface dipole moments, creating an electronic transformation between the n-type-like and p-type-like feature. The two inflection points correspond to the critical voltage of dipole rotation. The transformation thus forms an abnormal I-V hysteresis behavior in MAPbBr3.
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Chen, Yu-Ming, and 陳郁民. "Seismic Behavior of Rotational Hysteretic Energy-Dissipated Systems Incorporating Displacement-Magnification Mechanisms." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/49941983815376602261.

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碩士
國立交通大學
土木工程系所
105
Energy dissipation systems are being increasingly employed in Taiwan to provide enhanced seismic protection for new and retrofit building and bridge construction. The hardware utilized includes yielding steel devices, friction devices, visco-elastic solid devices, and mostly, so far, fluid viscous devices. This hardware has been used in either diagonal or chevron brace configurations. This study presents some new configurations that utilize displacement-magnification mechanisms to substantially magnify the effect of a novel rotational hysteretic energy-dissipated device incorporating with a displacement magnification mechanism and visco-elastic materials or high-damping rubber so that it can be utilized effectively in applications of small structural drift. In this study, a toggle-brace-damper configuration with rotational visco-elastic dampers (RVED) directly installed to the beam–column joints is presented. To facilitate practical applications, a procedure for determining the relationship between the displacement magnification factor and the geometry of the toggle-brace mechanism is established. Prototype tests, and shaking table tests are conducted to investigate the seismic responses of a large scale three-story steel model structure with and without RVEDs. Structural dynamic analyses are also used to demonstrate the utility of the proposed rotational hysteretic energy-dissipated devices. And the seismic design procedure and simulation technique for buildings installed with the rotational hysteretic energy-dissipated devices would be also proposed in this plan.
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Book chapters on the topic "Rotational hysteresis"

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Arrott, A. S., T. L. Templeton, and Y. Yoshida. "Rotational Hysteresis in Small Magnetic Particles." In Nanophase Materials, 663–74. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-1076-1_68.

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Bertotti, Giorgio. "Coherent Rotation." In Hysteresis in Magnetism, 225–54. Elsevier, 1998. http://dx.doi.org/10.1016/b978-012093270-2/50057-x.

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"Moment-rotation hysteresis for end-." In Connections in Steel Structures, 389–96. CRC Press, 1988. http://dx.doi.org/10.1201/9781482286427-150.

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Kukreti, Anant R., and Ali Abolmaali. "Moment-Rotation Hysteresis Behavior of Semi-Rigid Steel Building Frame Connections." In Impact And Friction Of Solids, Structures And Intelligent Machines, 39–42. WORLD SCIENTIFIC, 2000. http://dx.doi.org/10.1142/9789812792518_0009.

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Palla, A., M. Tatalias, and D. Straumann. "Hysteresis effects of the subjective visual vertical during continuous quasi-static whole-body roll rotation." In Progress in Brain Research, 271–75. Elsevier, 2008. http://dx.doi.org/10.1016/s0079-6123(08)00638-9.

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Kishi, N., M. Komuro, and W. Chen. "Elasto-plastic FE analysis on hysteretic moment-rotation behavior of top- and seat-angle connections." In Structures & Architecture, 173–74. CRC Press, 2010. http://dx.doi.org/10.1201/b10428-82.

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Conference papers on the topic "Rotational hysteresis"

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Tobise, Masahiro, Tomoyuki Ogawa, and Shin Saito. "Rotational Hysteresis Loss Analysis for Randomly Oriented A”-Fe16N2 Nanoparticles Assembly." In 2016 International Conference of Asian Union of Magnetics Societies (ICAUMS). IEEE, 2016. http://dx.doi.org/10.1109/icaums.2016.8479907.

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Wysiocki, J. J., and M. Leonowicz. "Magnetic Rotational Hysteresis Energy In Rapidly Solidified Nd-Fe-B magnets." In 1993 Digests of International Magnetics Conference. IEEE, 1993. http://dx.doi.org/10.1109/intmag.1993.642720.

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Alenborn, Kim Are, Andreas Klausen, Sondre Sanden Tordal, and Hamid Reza Karimi. "Firefly optimization used to identify hysteresis parameter on rotational MR-damper." In 2014 International Conference on Mechatronics and Control (ICMC). IEEE, 2014. http://dx.doi.org/10.1109/icmc.2014.7231979.

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Harrison, S. A., R. Street, J. R. Budge, and S. K. Jones. "A simple method of measuring magnetic rotational hysteresis losses in isotropic media." In IEEE International Magnetics Conference. IEEE, 1999. http://dx.doi.org/10.1109/intmag.1999.837304.

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Salz, W., M. Birkfeld, and K. A. Hempel. "Calculation Of Eddy Current Loss In Elecrical Steel Sheet Considering Rotational Hysteresis." In 1993 Digests of International Magnetics Conference. IEEE, 1993. http://dx.doi.org/10.1109/intmag.1993.642174.

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Lisfi, A., and J. C. Lodder. "Angular studies and rotational hysteresis analysis in barium ferrite films with perpendicular anisotropy." In IEEE International Magnetics Conference. IEEE, 1999. http://dx.doi.org/10.1109/intmag.1999.837244.

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Dost, Philip, Michael Schael, and Constantinos Sourkounis. "Electric vehicle application of rotational space vector hysteresis control with different electric motors." In IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society. IEEE, 2014. http://dx.doi.org/10.1109/iecon.2014.7048554.

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Li, Juan, Yanli Zhang, Dianhai Zhang, Ziyan Ren, and Chang Seop Koh. "Analysis of Rotational Hysteresis Property in a Transformer Core Based on an Inverse Jiles-Atherton Hysteresis Model Coupled with Finite Element Method." In 2020 23rd International Conference on Electrical Machines and Systems (ICEMS). IEEE, 2020. http://dx.doi.org/10.23919/icems50442.2020.9291026.

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Bonny, Daniel P., Stephen M. Howell, and Maury L. Hull. "A Computational Analysis of Error in Locating the Rotational Axes of the Tibiofemoral Joint With an Instrumented Spatial Linkage." In ASME 2012 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/sbc2012-80394.

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A method to measure the two kinematic axes of the tibiofemoral joint, the flexion-extension (F-E) axis and longitudinal rotation (LR) axis [1], was developed by Gatti [2]. This method used an instrumented spatial linkage (ISL), a series of six instrumented revolute joints that can measure motion between two rigid bodies. While Gatti’s method demonstrated success in locating the F-E and LR axes, defining the axes and their errors using anatomically relevant coordinate systems would improve clinical relevance. While errors due to revolute joint transducer resolution were computed, errors due to nonlinearity and hysteresis in the transducers were not examined, and errors due to different applied tibiofemoral motions were not examined. Thus the objective was to computationally determine, using anatomically relevant coordinate systems, the errors in locating the F-E and LR axes due to nonlinearity and hysteresis in the revolute joint transducers for three different simulations of applied tibiofemoral motion.
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Kolansky, Jeremy, Pablo Tarazaga, and John Ohanian. "Experimental Implementation of Opposed SMA Wires for Actuator Control." In ASME 2013 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/smasis2013-3015.

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Shape Memory Alloys (SMA) have shown their potential as linear actuators. The study conducted here investigates the use of SMA wires as linear actuators for the control of a rotational actuator. The SMA wires are attached to the sides of the actuator to generate opposing forces which are used to control the position of the actuator. In this study the capabilities of this mechanism are demonstrated through tracking of a control path. This mechanism also serves to highlight many effects of SMA wires not commonly discussed: the interaction of opposing hysteresis curves and their effects on the trajectory of the system, the effects of accelerated cooling rates on the hysteresis curves of SMA wires, and the benefits to response time because of the opposing SMA wires.
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