124,045 research outputs found
Antiferromagnetic correlation in the half-filled strongly correlated electron models at nonzero temperature: A rigorous result
No full textAs an extension of our previous rigorous investigation on the spin correlations in the ground states of the half-filled Hubbard model and the periodic Anderson model [G. S. Tian, Phys. Rev. B 50, 6246 (1994)], in the present paper we study the behavior of these correlation functions at finite temperature. We show rigorously that, at any T not equal0, the predominant spin correlations in these systems are antiferromagnetic. Furthermore, based on this result, we also show that a quasi-one (or two)-dimensional itinerant electron ferrimagnet must have a gapless branch of ferromagnetic excitations. This conclusion is consistent with the previous results derived by the spin-wave theory.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000169283000058&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Physics, Condensed MatterSCI(E)10ARTICLE22null6
Dans le Tian Chan Russe
No full textSaint-Yves G. Dans le Tian Chan Russe. In: Annales de Géographie, t. 9, n°44, 1900. pp. 119-140
Letter, [Author unclear] to Paulina T. Merritt
No full textHandwritten letter to Paulina Merritt from an unknown author, October 1, 1876.
Author correction to "Enhanced property of thin cuprous oxide film prepared through green synthetic route"(Vol 32, 365, 2019)
No full textEl Kasmi A, Vieker H, Wu L-nan, Beyer A, Chafik T, Tian Z-yu. Author correction to "Enhanced property of thin cuprous oxide film prepared through green synthetic route"(Vol 32, 365, 2019). Chinese Journal of Chemical Physics. 2024;37(4):571.This correction adds some information to our publication [Chin. J. Chem. Phys. 32, 365-372 (2019)] that we previously missed to include
[Tian qing wen jing shu 天 請 問 經疏.]
No full textDevatā-sūtra, cf. Tian qing wen jing.Fo shuo tian qingwen jing 佛 說 天 請 問 經, cf. Tian qing wen jing.Tian qing wen jing天 請 問 經Tian qing wen jing shu 天 請 問 經 疏Numérisation effectuée à partir d'un document original.[Commentaires du Tianqing wen jing 天 請 問 經, (T . 592)] En 1 j., déb. mutilé, copie inachevée. Col. 1 à 209 non éd. in T .Pour les col. 210 à 212, cf. T .2786, vol. 85, p. 562 c 2-6, qui donne la suite et la fin de ce texte d'aprèsune éd. de Péking, pp. 562 c 6-565 c. Bonne écr. Pour le car.guo 國, graphie usuelle et graphie 圀 particulièreau règne de l'impératrice Wu. Rares additions et ratures. 212 col. en tout. 20à 22 col. par f., 22 à 26 car. par col. Marges sup. et inf. non tracées, 0,1 à1,3 cm. Réglure par pliage
Compressible Rayleigh-Taylor turbulent mixing under different acceleration histories
No full textCompressible Rayleigh-Taylor turbulent mixing (CRTM) induced by Rayleigh-Taylor instability occurs when a compressible fluid of heavy density is accelerated or supported against gravity by a compressible fluid of light density, and is of fundamental importance in applications from combustion, to inertial confinement fusion, and to astrophysics. Traditionally, CRTFs are studied under constant acceleration histories. Due to the nature of the processes, however, it is necessary to study CRTF under general acceleration histories g(t). In this aspect, the evolution of Rayleigh-Taylor turbulent mixing under complex acceleration histories, including changes in signs, have been studied numerically[1] and experimentally[2] for incompressible flows, leaving an open question on that of compressible flows. In fact, most engineering problems are compressible. In addition, the available engineering turbulence models cannot capture the variation of mixing width for CRTM with complex acceleration histories, such as the gravity reversal. In order to better understanding the dynamic of CRTM under different variation histories, several DNS cases with different acceleration histories have been conducted and analyzed
Investigation of code reconfigurable fibre Bragg gratings for Optical Code Division Multiple Access (OCDMA) and Optical Packet Switching (OPS) Networks
No full textThis thesis documents my work in the telecommunication system laboratory at the Optoelectronics Research Centre, towards the implementation of code reconfigurable OCDMA and all-optical packet switching nodes based on fibre Bragg grating (FBG) technology. My research work involves characterizing the performance of various gratings, specifically high reflectivity, short chip duration, long code sequences, multiple phase level and tunable superstructured fiber Bragg gratings (SSFBGs), by using the recently proposed Frequency-Resolved Optical Gating technique based on Electro-Absorption Modulator (EAM-FROG). This technology can obtain the complex code profile along the grating, making it a powerful method to understand the thermally-induced code-reconfigurable grating. Efforts have been made to improve the grating design to achieve better system performance. Three different types of FBGs optical encoder/decoder, e.g. conventional discrete phaseshift SSFBGs, code-reconfigurable gratings, and novel continuous phase-shift SSFBGs, have been investigated comparatively, as well as their performance in various optical coding/decoding systems. This thesis also discusses the possibility of reducing multiple access interference (MAI) using a Two-Photon Absorption (TPA) process. The advanced grating devices enable the improvement of system performance. A dynamically reconfigurable optical packet processing system and a 16-channel reconfigurable OCDMA/DWDM system with 50GHz DWDM intervals has been demonstrated.These results highlight the feasibility of FBG-based optical coding/decoding techniques, with improved system flexibility and sustainability
Process fault prognosis using a fuzzy-adaptive unscented Kalman predictor
No full textBy monitoring the future process status via information prediction, process fault prognosis is able to give an early alarm and therefore prevent faults, when the faults are still in their early stages. A fuzzy-adaptive unscented Kalman filter (FAUKF)-based predictor is proposed to improve the tracking and forecasting capability for process fault prognosis. The predictor combines the strong tracking concept and fuzzy logic idea. Similar to the standard adaptive unscented Kalman filter (AUKF) that employs an adaptive parameter to correct the estimation error covariance, a Takagi–Sugeno fuzzy logic system is designed to provide a better adaptive parameter for smoothing this regulation. Compared with the standard AUKF, the proposed FAUKF has the same strong tracking ability but does not suffer from the drawback of serious tracking fluctuation. Two simulation examples demonstrate the effectiveness of the proposed predictor
Etudes glaciaires dans le Caucase, le Tian-Chan et l'Altaï
No full textZimmermann Maurice. Etudes glaciaires dans le Caucase, le Tian-Chan et l'Altaï. In: Annales de Géographie, t. 22, n°121, 1913. pp. 107-109
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