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Добірка наукової літератури з теми "Weakening of the geomagnetic field"

Автор: Grafiati

Опубліковано: 30 травня 2022

Оновлено: 31 травня 2022

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Статті в журналах з теми "Weakening of the geomagnetic field"

Brown, Maxwell, Monika Korte, Richard Holme, Ingo Wardinski, and Sydney Gunnarson. "Earth’s magnetic field is probably not reversing." Proceedings of the National Academy of Sciences 115, no. 20 (April 30, 2018): 5111–16. http://dx.doi.org/10.1073/pnas.1722110115.

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The geomagnetic field has been decaying at a rate of ∼5% per century from at least 1840, with indirect observations suggesting a decay since 1600 or even earlier. This has led to the assertion that the geomagnetic field may be undergoing a reversal or an excursion. We have derived a model of the geomagnetic field spanning 30–50 ka, constructed to study the behavior of the two most recent excursions: the Laschamp and Mono Lake, centered at 41 and 34 ka, respectively. Here, we show that neither excursion demonstrates field evolution similar to current changes in the geomagnetic field. At earlier times, centered at 49 and 46 ka, the field is comparable to today’s field, with an intensity structure similar to today’s South Atlantic Anomaly (SAA); however, neither of these SAA-like fields develop into an excursion or reversal. This suggests that the current weakened field will also recover without an extreme event such as an excursion or reversal. The SAA-like field structure at 46 ka appears to be coeval with published increases in geomagnetically modulated beryllium and chlorine nuclide production, despite the global dipole field not weakening significantly in our model during this time. This agreement suggests a greater complexity in the relationship between cosmogenic nuclide production and the geomagnetic field than is commonly assumed.

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Roman, Adam, and Barbara Tombarkiewicz. "Prolonged weakening of the geomagnetic field (GMF) affects the immune system of rats." Bioelectromagnetics 30, no. 1 (January 2009): 21–28. http://dx.doi.org/10.1002/bem.20435.

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Ben-Yosef, Erez, Michael Millman, Ron Shaar, Lisa Tauxe, and Oded Lipschits. "Six centuries of geomagnetic intensity variations recorded by royal Judean stamped jar handles." Proceedings of the National Academy of Sciences 114, no. 9 (February 13, 2017): 2160–65. http://dx.doi.org/10.1073/pnas.1615797114.

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Earth’s magnetic field, one of the most enigmatic physical phenomena of the planet, is constantly changing on various time scales, from decades to millennia and longer. The reconstruction of geomagnetic field behavior in periods predating direct observations with modern instrumentation is based on geological and archaeological materials and has the twin challenges of (i) the accuracy of ancient paleomagnetic estimates and (ii) the dating of the archaeological material. Here we address the latter by using a set of storage jar handles (fired clay) stamped by royal seals as part of the ancient administrative system in Judah (Jerusalem and its vicinity). The typology of the stamp impressions, which corresponds to changes in the political entities ruling this area, provides excellent age constraints for the firing event of these artifacts. Together with rigorous paleomagnetic experimental procedures, this study yielded an unparalleled record of the geomagnetic field intensity during the eighth to second centuries BCE. The new record constitutes a substantial advance in our knowledge of past geomagnetic field variations in the southern Levant. Although it demonstrates a relatively stable and gradually declining field during the sixth to second centuries BCE, the new record provides further support for a short interval of extreme high values during the late eighth century BCE. The rate of change during this “geomagnetic spike” [defined as virtual axial dipole moment > 160 ZAm2 (1021 Am2)] is further constrained by the new data, which indicate an extremely rapid weakening of the field (losing ∼27% of its strength over ca. 30 y).

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Pavlov, A. V., S. Fukao, and S. Kawamura. "A modeling study of ionospheric F2-region storm effects at low geomagnetic latitudes during 17-22 March 1990." Annales Geophysicae 24, no. 3 (May 19, 2006): 915–40. http://dx.doi.org/10.5194/angeo-24-915-2006.

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Abstract. We have presented a comparison between the modeled NmF2 and hmF2, and NmF2 and hmF2, which were observed in the low-latitude ionosphere simultaneously by the Kokubunji, Yamagawa, Okinawa, Manila, Vanimo, and Darwin ionospheric sounders, by the middle and upper atmosphere (MU) radar during 17-22 March 1990, and by the Arecibo radar for the time period of 20-22 March 1990. A comparison between the electron and ion temperatures measured by the MU and Arecibo radars and those produced by the model of the ionosphere and plasmasphere is presented. The empirical zonal electric field, the meridional neutral wind taken from the HWM90 wind model, and the NRLMSISE-00 neutral temperature and densities are corrected so that the model results agree reasonably with the ionospheric sounder observations, and the MU and Arecibo radar data. It is proved that the nighttime weakening of the equatorial zonal electric field (in comparison with that produced by the empirical model of Fejer and Scherliess (1997) or Scherliess and Fejer (1999)), in combination with the corrected wind-induced plasma drift along magnetic field lines, provides the development of the nighttime enhancements in NmF2 observed over Manila during 17-22 March 1990. As a result, the new physical mechanism of the nighttime NmF2 enhancement formation close to the geomagnetic equator includes the nighttime weakening of the equatorial zonal electric field and equatorward nighttime plasma drift along magnetic field lines caused by neutral wind in the both geomagnetic hemispheres. It is found that the latitudinal positions of the crests depend on the E×B drift velocity and on the neutral wind velocity. The relative role of the main mechanisms of the equatorial anomaly suppression observed during geomagnetic storms is studied for the first time in terms of storm-time variations of the model crest-to-trough ratios of the equatorial anomaly. During most of the studied time period, a total contribution from meridional neutral winds and variations in the zonal electric field to the equatorial anomaly changes is larger than that from geomagnetic storm disturbances in the neutral temperature and densities. Vibrationally excited N2 and O2 promote the equatorial anomaly enhancement during the predominant part of the studied time period, however, the role of vibrationally excited N2 and O2 in the development of the equatorial anomaly is not significant. The asymmetries in the neutral wind and densities relative to the geomagnetic equator are responsible for the north-south asymmetry in NmF2 and hmF2, and for the asymmetry between the values of the crest-to-trough ratios of the Northern and Southern Hemispheres. The model simulations provide evidence in favor of an asymmetry in longitude of the energy input into the auroral region of the Northern Hemisphere on 21 March 1990.

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Zhou, Xu, XinAn Yue, Han-Li Liu, Yong Wei, and YongXin Pan. "Response of atmospheric carbon dioxide to the secular variation of weakening geomagnetic field in whole atmosphere simulations." Earth and Planetary Physics 5, no. 4 (2021): 1–10. http://dx.doi.org/10.26464/epp2021040.

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Pavlov, A. V., S. Fukao, and S. Kawamura. "<i>F</i>-region ionospheric perturbations in the low-latitude ionosphere during the geomagnetic storm of 25-27 August 1987." Annales Geophysicae 22, no. 10 (November 3, 2004): 3479–501. http://dx.doi.org/10.5194/angeo-22-3479-2004.

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Abstract. We have presented a comparison between the modeled NmF2 and hmF2, and NmF2 and hmF2 which were observed at the equatorial anomaly crest and close to the geomagnetic equator simultaneously by the Akita, Kokubunji, Yamagawa, Okinawa, Manila, Vanimo, and Darwin ionospheric sounders and by the middle and upper atmosphere (MU) radar (34.85° N, 136.10° E) during the 25-27 August 1987 geomagnetically storm-time period at low solar activity near 201°, geomagnetic longitude. A comparison between the electron and ion temperatures measured by the MU radar and those produced by the model of the ionosphere and plasmasphere is presented. The corrections of the storm-time zonal electric field, EΛ, from 16:30 UT to 21:00 UT on 25 August bring the modeled and measured hmF2 into reasonable agreement. In both hemispheres, the meridional neutral wind, W, taken from the HWW90 wind model and the NRLMSISE-00 neutral temperature, Tn, and densities are corrected so that the model results agree with the ionospheric sounders and MU radar observations. The geomagnetic latitude variations in NmF2 on 26 August differ significantly from those on 25 and 27 August. The equatorial plasma fountain undergoes significant inhibition on 26 August. This suppression of the equatorial anomaly on 26 August is not due to a reduction in the meridional component of the plasma drift perpendicular to the geomagnetic field direction, but is due to the action of storm-time changes in neutral winds and densities on the plasma fountain process. The asymmetry in W determines most of the north-south asymmetry in hmF2 and NmF2 on 25 and 27 August between about 01:00-01:30 UT and about 14:00 UT when the equatorial anomaly exists in the ionosphere, while asymmetries in W, Tn, and neutral densities relative to the geomagnetic equator are responsible for the north-south asymmetry in NmF2 and hmF2 on 26 August. A theory of the primary mechanisms causing the morning and evening peaks in the electron temperature, Te, is developed. An appearance, magnitude variations, latitude variations, and a disappearance of the morning Te peaks during 25-27 August are caused by variations in EΛ, thermospheric composition, Tn, and W. The magnitude of the evening Te peak and its time location are decreased with the lowering of the geomagnetic latitude due to the weakening of the effect of the plasma drift caused by W on the electron density. The difference between 25 August and 26-27 August in an appearance, magnitude and latitude variations, and a disappearance of the evening Te peak is caused by variations in W, the thermospheric composition, Tn, and EΛ.

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Subrahmanyam, P., A. R. Jain, L. Singh, and S. C. Garg. "Role of neutral wind and storm time electric fields inferred from the storm time ionization distribution at low latitudes: in-situ measurements by Indian satellite SROSS-C2." Annales Geophysicae 23, no. 10 (November 30, 2005): 3289–99. http://dx.doi.org/10.5194/angeo-23-3289-2005.

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Abstract. Recently, there has been a renewal of interest in the study of the effects of solar weather events on the ionization redistribution and irregularity generation. The observed changes at low and equatorial latitudes are rather complex and are noted to be a function of location, the time of the storm onset and its intensity, and various other characteristics of the geomagnetic storms triggered by solar weather events. At these latitudes, the effects of geomagnetic storms are basically due to (a) direct penetration of the magnetospheric electric fields to low latitudes, (b) development of disturbance dynamo, (c) changes in atmospheric neutral winds at ionospheric level and (d) changes in neutral composition triggered by the storm time atmospheric heating. In the present study an attempt is made to further understand some of the observed storm time effects in terms of storm time changes in zonal electric fields and meridional neutral winds. For this purpose, observations made by the Retarding Potential Analyzer (RPA) payload on board the Indian satellite SROSS-C2 are examined for four prominent geomagnetic storm events that occurred during the high solar activity period of 1997-2000. Available simultaneous observations, from the GPS satellite network, are also used. The daytime passes of SROSS-C2 have been selected to examine the redistribution of ionization in the equatorial ionization anomaly (EIA) region. In general, EIA is observed to be weakened 12-24 h after the main phase onset (MPO) of the storm. The storm time behaviour inferred by SROSS-C2 and the GPS satellite network during the geomagnetic storm of 13 November 1998, for which simultaneous observations are available, is found to be consistent. Storm time changes in the delay of received GPS signals are noted to be ~1-3 m, which is a significant component of the total delay observed on a quiet day. An attempt is made to identify and delineate the effects of a) meridional neutral winds, b) the development of the ring currents and c) the disturbance dynamo electric fields on the low latitude ionization distribution. The weakening of the EIA is noted to be primarily due to the decrease in the eastward electric fields driving the equatorial fountain during the daytime. The meridional neutral winds are also noted to play an important role in redistribution of ionization in the EIA region. The present results demonstrate that storm time latitudinal distribution of ionization in this region can be better understood by taking into account the meridional winds in addition to E×B drifts.

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Kauristie, K., M. V. Uspensky, N. G. Kleimenova, O. V. Kozyreva, M. M. J. L. Van De Kamp, S. V. Dubyagin, and S. Massetti. "Equivalent currents associated with morning-sector geomagnetic Pc5 pulsations during auroral substorms." Annales Geophysicae 34, no. 4 (April 7, 2016): 379–92. http://dx.doi.org/10.5194/angeo-34-379-2016.

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Abstract. Space and time variations of equivalent currents during morning-sector Pc5 pulsations (T ∼ 2–8 min) on 2 days (18 January and 19 February 2008) are studied in the context of substorm activity with THEMIS and MIRACLE ground-based instruments and THEMIS P3, P5, and P2 probes. These instruments covered the 22:00–07:00 magnetic local time during the analyzed events. In these cases abrupt changes in the Pc5 amplitudes, intensifications and/or weakenings, were recorded some minutes after auroral breakups in the midnight sector. We analyze three examples of Pc5 changes with the goal to resolve whether substorm activity can have an effect on Pc5 amplitude or not. In two cases (on 19 February) the most likely explanation for Pc5 amplitude changes comes from the solar wind (changes in the sign of interplanetary magnetic field Bz). In the third case (on 18 January) equivalent current patterns in the morning sector show an antisunward-propagating vortex which replaced the Pc5-related smaller vortices and consequently the pulsations weakened. We associate the large vortex with a field-aligned current system due to a sudden, although small, drop in solar wind pressure (from 1 to 0.2 nPa). However, the potential impact of midnight substorm activity cannot be totally excluded in this case, because enhanced fluxes of electrons with high enough energies (∼ 280 keV) to reach the region of Pc5 within the observed delay were observed by THEMIS P2 at longitudes between the midnight and morning-sector instrumentation.

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Amrhein, Marco, Philip Krein, Patrick Chapman, and Brenda Fierro. "Field Weakening Alternative." IEEE Industry Applications Magazine 13, no. 6 (November 2007): 28–37. http://dx.doi.org/10.1109/mia.2007.907208.

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Jurica, Jan. "Geomagnetic field mapping." Journal of the ASB Society 1, no. 1 (December 28, 2020): 22–29. http://dx.doi.org/10.51337/jasb20201228003.

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This work focuses on creating maps of the geomagnetic field and areas of increased cosmic radiation surrounding the Earth. Data were measured by Proba-V satellite at Low-Earth orbit 820 kilometres above the Earth during 2015. The actual measured data were compared with the calculated magnetic values. The created maps serve to a better understanding of the shape of the geomagnetic field and show magnetic equator, north magnetic pole and more. The map confirms that the area of the South Atlantic Anomaly corresponds with the weakest area of the geomagnetic field. Maps of different time periods of 2015 show small changes in the shape of the geomagnetic field during a year. Increased attention was paid to June 2015, when solar flares were passing near the Earth. The observation confirms that solar flares have a significant effect on the shape of the geomagnetic field.

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Більше джерел

Дисертації з теми "Weakening of the geomagnetic field"

Грецких, Светлана Владимировна. "Ослабление статического геомагнитного поля ферромагнитными элементами домов". Thesis, Государственное учреждение "Институт технических проблем магнетизма НАН Украины", 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/21435.

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Диссертация на соискание ученой степени кандидата технических наук по специальности 05.09.05 – теоретическая электротехника. – Национальный технический университет "Харьковский политехнический институт", Харьков, 2016. Диссертация посвящена математическому моделированию явления ослабления статического геомагнитного поля (ГМП) в помещениях жилых домов и разработке рекомендаций по методам его нормализации до безопасного уровня. Полученные в диссертации результаты в совокупности составляют существенный вклад в решение научно-прикладной задачи теоретической электротехники по моделированию явления ослабления ГМП стальными ферромагнитными элементами конструкций домов и разработки рекомендаций по методам нормализации ГМП в помещениях до безопасного для людей уровня. Основные результаты выполненных в диссертации исследований и практических разработок использованы при выполнении тематического плана ГУ "ИТПМ НАН Украины", в Институте гигиены и медицинской экологии им. А. Н. Марзеева НАМН Украины при разработке "Государственных санитарных правил и норм защиты населения от влияния электромагнитных излучений", при проектировании и строительстве в г. Харькове современных каркасно-монолитных жилых домов с безопасными условиями проживания (ООО "АВУАР"). Результаты работы рекомендованы к применению научным и промышленным учреждениям и предприятиям, выполняющим разработку методов и средств моделирования, расчета и нормализации статического ГМП в жилых домах, проектирующим современные жилые дома с безопасными условиями проживания по магнитному полю.
Thesis for scientific degree of candidate of technical sciences, specialty 05.09.05 – theoretical electrical engineering. – National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2016. The thesis is devoted to mathematical modeling of the phenomenon of weakening of the static geomagnetic field (GMF) in residential homes and to the development of recommendations on how to normalize it to a safe level. The modeling of weakening of the GMF was performed with the help of the equivalent charges method. The cylindrical ferromagnetic column was taken as an example. In the framework of this technique the problem of calculation of the GMF’s induction weakened by extended ferromagnetic elements was solved. The physical parameters of the ferromagnetic column which effect the weakening of GMF are determined. The conditions under which GMF is reduced to the safety level are also determined. This is due to the changes of the GMF’s geometry and reducing of initial magnetic permeability of its material. The Arcadiev method of the effective magnetic permeability for modeling of magneticfield of reinforced concrete columns and intermediate floors was developed. The numerical modeling of static GMF in premises of houses with reinforced concrete structures was performed. The numerical results were experimentally confirmed. The recommendations for normalizing of GMF for creating safe and comfortable living conditions are given. These recommendations should be taken into account in designing modern premises of houses.

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Грецьких, Світлана Володимирівна. "Ослаблення статичного геомагнітного поля феромагнітними елементами будинків". Thesis, НТУ "ХПІ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/21433.

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Анотація:

Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.09.05 – теоретична електротехніка. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2016. Дисертація присвячена математичному моделюванню явища ослаблення статичного геомагнітного поля (ГМП) в приміщеннях житлових будинків та розробці рекомендацій з методів його нормалізації до безпечного рівня. На прикладі циліндричної феромагнітної колони проведено моделювання ослаблення ГМП за допомогою методу еквівалентних (фіктивних) магнітних зарядів та розв’язано задачу розрахунку індукції ГМП, ослабленого протяжними феромагнітними елементами. Визначенні фізичні параметри феромагнітної колони, що впливають на інтенсивність ослаблення ГМП поблизу її поверхні, та умови зменшення до безпечного рівня інтенсивності ослаблення ГМП за рахунок зміни геометрії колони та зменшення початкової магнітної проникності її матеріалу. Здійснено розвиток методу ефективної магнітної проникності Аркадьєва для моделювання магнітного поля залізобетонних колон та міжповерхових перекриттів, армованих сталевим металопрокатом, та виконане чисельне моделювання інтенсивності ослаблення статичного ГМП в приміщеннях житлових будинків з несучими залізобетонними конструкціями і його верифікацію на основі результатів експерименту. Розроблені рекомендації з методів нормалізації ГМП при проектуванні сучасних житлових будинків для створення безпечних та комфортних умов проживання населення за статичним ГМП.
Thesis for scientific degree of candidate of technical sciences, specialty 05.09.05 – theoretical electrical engineering. – National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2016. The thesis is devoted to mathematical modeling of the phenomenon of weakening of the static geomagnetic field (GMF) in residential homes and to the development of recommendations on how to normalize it to a safe level. The modeling of weakening of the GMF was performed with the help of the equivalent charges method. The cylindrical ferromagnetic column was taken as an example. In the framework of this technique the problem of calculation of the GMF’s induction weakened by extended ferromagnetic elements was solved. The physical parameters of the ferromagnetic column which effect the weakening of GMF are determined. The conditions under which GMF is reduced to the safety level are also determined. This is due to the changes of the GMF’s geometry and reducing of initial magnetic permeability of its material. The Arcadiev method of the effective magnetic permeability for modeling of magneticfield of reinforced concrete columns and intermediate floors was developed. The numerical modeling of static GMF in premises of houses with reinforced concrete structures was performed. The numerical results were experimentally confirmed. The recommendations for normalizing of GMF for creating safe and comfortable living conditions are given. These recommendations should be taken into account in designing modern premises of houses.

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Hutcheson, Kenneth Andrew. "Geomagnetic field modelling." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385503.

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Thorsen, Kjetil. "Mathematical Model of the Geomagnetic Field." Thesis, Norwegian University of Science and Technology, Department of Mathematical Sciences, 2006. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9329.

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Анотація:

First comes a description of a mathematical model of the geomagnetic field. Then some discussion of the classical non-uniqueness results of Backus. Further we look at more recent results concerning reconstruction of the geomagnetic field from intensity and the normal component of the field. New stability estimate for this reconstruction is obtained.

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Ryan, David Alexander. "The long term behaviour of the geomagnetic field." Thesis, University of Newcastle upon Tyne, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.519467.

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Livermore, R. A. "The time-average geomagnetic field since the late Palaeozoic." Thesis, University of East Anglia, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355532.

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Filippi, Enrico <1983&gt. "Turbulent Diffusion of the Geomagnetic Field and Dynamo Theories." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7471/.

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The thesis deals with the Dynamo Theories of the Earth’s Magnetic Field and mainly deepens the turbulence phenomena in the fluid Earth’s core. Indeed, we think that these phenomena are very important to understand the recent decay of the geomagnetic field. The thesis concerns also the dynamics of the outer core and some very rapid changes of the geomagnetic field observed in the Earth’s surface and some aspects regarding the (likely) isotropic turbulence in the Magnetohydrodynamics. These topics are related to the Dynamo Theories and could be useful to investigate the geomagnetic field trends.

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Finnman, Jonas, and Erik Eketorp. "Design and Manufacturing of IPM Synchronous Motor for Field Weakening Operation." Thesis, KTH, Skolan för elektro- och systemteknik (EES), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-128511.

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Rotor designs for permanent magnet synchronous machines suitable for field weakening operation have been evaluated for use with an existing drive system. The designs have been simulated with the FEM-based software Finite Element Method Magnetics (FEMM). Based on the results two different internal magnet rotors have been constructed and tested. Both designs significantly improved the speed range while maintaining or improving magnet utilisation. The implementation of field weakening algorithms in drive electronics is complex and need thorough optimisation for stable operation. Internal permanent magnet rotors are a good alternative to surface mounted designs and enables a wider speed range through improved field weakening capabilities.

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Antunes, Fernando Luiz Marcelo. "A microprocessor-controlled DC servo-drive with spill-over field weakening." Thesis, Loughborough University, 1990. https://dspace.lboro.ac.uk/2134/33224.

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The thesis presents a speed-control scheme for a separately-excited DC motor using a microprocessor. The control strategy incorporates both armature-voltage control and spill-over field weakening. The armature voltage is controlled in closed loop using a lead term in series with an integral term. The analogue Lead-Integral (LI) controller parameters were obtained and optimised by observing the system time response in successive digital simulations. The parameters determined provide the motor with a fast response and minimum speed overshoot during transient operations. The analogue LI controller was emulated to form a digital filter using the bilinear transformation and implemented in a 16-bit microprocessor using floating point arithmetic.

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Zhang, Yuan. "Sensorless Vector Control and Field Weakening Operation of Permanent Magnet Synchronous Machines." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1291219704.

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Книги з теми "Weakening of the geomagnetic field"

Glaβmeier, Karl-Heinz, Heinrich Soffel, and Jörg F. W. Negendank. Geomagnetic Field Variations. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-76939-2.

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Sh, Dolginov Sh. Research on the geomagnetic field. Washington, DC: National Aeronautics and Space Administration, 1989.

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Musaba, L. Design and performance of synchronous motor drives with field-weakening. Manchester: UMIST, 1996.

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Janoo, Vincent C. PCC airfield pavement response during thaw-weakening periods: A field study. [Hanover, N.H.]: US Army Corps of Engineers, Cold Regions Research & Engineering Laboratory, 1996.

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Livermore, R. A. The time-average geomagnetic field since the late Palaeozoic. Norwich: University of East Anglia, 1985.

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Barraclough, D. R. International Geomagnetic Reference Field 1985: Grid-point values and charts. Aberdeen, Scotland: Secretary General of IAGA, 1986.

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Constable, Catherine. Final report on geomagnetic field models incorporating physical constraints on the secular variation. [Washington, DC: National Aeronautics and Space Administration, 1993.

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Shui xia di ci dao hang ji shu: Technologies on Underwater Geomagnetic Field Navigation. Beijing: Guo fang gong ye chu ban she, 2013.

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Pyrhönen, Olli. Analysis and control of excitation, field weakening and stability in direct torque controlled electrically excited synchronous motor drives. Lappeenranta, Finland: Lappeenranta University of Technology, 1998.

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Xanthakis, John N. Geomagnetic field variation as inferred from archaeomagnetism in Greece and palaeomagnetism in British lake sediments since 7000 B.C. Athēnai: Grapheion Dēmosieumatōn tēs Akadēmias Athēnōn, 1991.

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Частини книг з теми "Weakening of the geomagnetic field"

Schettino, Antonio. "The Geomagnetic Field." In Quantitative Plate Tectonics, 103–41. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-09135-8_4.

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Chambodut, Aude. "Geomagnetic Field, IGRF." In Encyclopedia of Solid Earth Geophysics, 379–80. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-90-481-8702-7_111.

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Busse, Friedrich H. "Geomagnetic Field, Theory." In Encyclopedia of Solid Earth Geophysics, 394–401. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-90-481-8702-7_103.

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Busse, Friedrich H. "Geomagnetic Field, Theory." In Encyclopedia of Solid Earth Geophysics, 1–9. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-10475-7_103-1.

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Chambodut, Aude. "Geomagnetic Field, IGRF." In Encyclopedia of Solid Earth Geophysics, 1–3. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-10475-7_111-1.

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Busse, Friedrich H. "Geomagnetic Field, Theory." In Encyclopedia of Solid Earth Geophysics, 515–23. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-58631-7_103.

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Chambodut, Aude. "Geomagnetic Field, IGRF." In Encyclopedia of Solid Earth Geophysics, 500–502. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-58631-7_111.

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Fabian, Karl, and Roman Leonhardt. "Records of Paleomagnetic Field Variations." In Geomagnetic Field Variations, 65–106. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-76939-2_3.

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Wicht, Johannes, Stephan Stellmach, and Helmut Harder. "Numerical Models of the Geodynamo: From Fundamental Cartesian Models to 3D Simulations of Field Reversals." In Geomagnetic Field Variations, 107–58. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-76939-2_4.

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Vogt, Joachim, Miriam Sinnhuber, and May-Britt Kallenrode. "Effects of Geomagnetic Variations on System Earth." In Geomagnetic Field Variations, 159–208. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-76939-2_5.

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Тези доповідей конференцій з теми "Weakening of the geomagnetic field"

Mohanty, Pravata, K. P. Arunbabu, S. R. Dugad, S. K. Gupta, B. Hariharan, Y. Hayashi, P. Jagadeesan, et al. "Transient weakening of geomagnetic shield probed by GRAPES-3 experiment." In 35th International Cosmic Ray Conference. Trieste, Italy: Sissa Medialab, 2017. http://dx.doi.org/10.22323/1.301.0092.

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Eastham, F. "Operational features (cogging, field weakening)." In IEE Seminar on Permanent Magnet Materials-Fundamentals, Design and Application. IEE, 2000. http://dx.doi.org/10.1049/ic:20000458.

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Jian-jing Liu, He Zhang, and Li Chen. "Bilinear interpolation of geomagnetic field." In 2010 International Conference on Computer Application and System Modeling (ICCASM 2010). IEEE, 2010. http://dx.doi.org/10.1109/iccasm.2010.5620517.

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Xinhai, Jin, Zeng Yanneng, and Xu Dianguo. "Novel PMSM field-weakening control method." In IECON 2017 - 43rd Annual Conference of the IEEE Industrial Electronics Society. IEEE, 2017. http://dx.doi.org/10.1109/iecon.2017.8216637.

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Xie, Jiahao, A. P. Sakis Meliopoulos, Boqi Xie, Chiyang Zhong, and Kaiyu Liu. "Geoelectric Field Estimation during Geomagnetic Disturbances." In 2019 IEEE Power & Energy Society General Meeting (PESGM). IEEE, 2019. http://dx.doi.org/10.1109/pesgm40551.2019.8973571.

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Doneva, Blagica. "INTERACTION BETWEEN SEISMIC AND GEOMAGNETIC FIELD." In 14th SGEM GeoConference on SCIENCE AND TECHNOLOGIES IN GEOLOGY, EXPLORATION AND MINING. Stef92 Technology, 2014. http://dx.doi.org/10.5593/sgem2014/b11/s5.067.

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Kaji, Chinmaya V., Randy C. Hoover, and Shankarachary Ragi. "Underwater Navigation using Geomagnetic Field Variations." In 2019 IEEE International Conference on Electro Information Technology (EIT). IEEE, 2019. http://dx.doi.org/10.1109/eit.2019.8834192.

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Asimopolos, Natalia-Silvia. "INTERRELATIONS BETWEEN CLIMATE CHANGE AND GEOMAGNETIC FIELD MONITORIZED AT SURLARI GEOMAGNETIC OBSERVATORY." In 19th SGEM International Multidisciplinary Scientific GeoConference EXPO Proceedings. STEF92 Technology, 2019. http://dx.doi.org/10.5593/sgem2019v/4.2/s06.034.

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Kühn, G. J., and L. Loubser. "External Geomagnetic Field Variations And Magnetic Surveys." In 1st SAGA Biennial Conference and Exhibition. European Association of Geoscientists & Engineers, 1989. http://dx.doi.org/10.3997/2214-4609-pdb.222.029.

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Petroškevicius, Petras, Arūnas Buga, and Romuald Obuchovski. "Latest research on geomagnetic field in Lithuania." In The 9th International Conference "Environmental Engineering 2014". Vilnius, Lithuania: Vilnius Gediminas Technical University Press “Technika” 2014, 2014. http://dx.doi.org/10.3846/enviro.2014.237.

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Звіти організацій з теми "Weakening of the geomagnetic field"

Newitt, L. R., and G. V. Haines. The Canadian Geomagnetic Reference Field 1990. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1991. http://dx.doi.org/10.4095/132653.

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McLeod, Malcolm G. A Predicted Geomagnetic Field Model for Epoch 1990.0. Fort Belvoir, VA: Defense Technical Information Center, January 1993. http://dx.doi.org/10.21236/ada260669.

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Peter Damiano and J.R. Johnson. Electro Acceleration in a Geomagnetic Field Line Resonance. Office of Scientific and Technical Information (OSTI), August 2012. http://dx.doi.org/10.2172/1062556.

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McLeod, M. G. A Predictive Geomagnetic Field Model for Epoch 1990.5. Fort Belvoir, VA: Defense Technical Information Center, August 1990. http://dx.doi.org/10.21236/ada226491.

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Newitt, L. R., and G. V. Haines. Instructions for the production of the Canadian Geomagnetic Reference Field. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1990. http://dx.doi.org/10.4095/225659.

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Newitt, L. R., and G. V. Haines. Notes for users of software for the Canadian Geomagnetic Reference Field. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1990. http://dx.doi.org/10.4095/225654.

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Nikitina, L., and L. Trichtchenko. Extreme values statistical assessment for geomagnetic and geoelectric field variations for Alberta. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2015. http://dx.doi.org/10.4095/296956.

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Kleimenova, Natalia G., A. Odzimek, S. Michnowski, and M. Kubicki. Geomagnetic Storms and Substorms as Space Weather I nfluence on Atmospheric Electric Field Variations. Balkan, Black Sea and Caspian Sea Regional Network on Space Weather Studies, November 2018. http://dx.doi.org/10.31401/sungeo.2018.01.14.

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Storini, M., D. F. Smart, and M. A. Shea. Summary of LARC Particle Asymptotic Changes From Geomagnetic Reference Field Models: 1955 to 1995. Fort Belvoir, VA: Defense Technical Information Center, January 2002. http://dx.doi.org/10.21236/ada423117.

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Onovughe, Elvis. Usage of RC index as a Good Representation for Characterising Rapid Variation Signals in Geomagnetic Field Studiess. Balkan, Black sea and Caspian sea Regional Network for Space Weather Studies, April 2018. http://dx.doi.org/10.31401/sungeo.2018.01.11.

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