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Enhancement of the angular rotation measurement sensitivity based on SU(2)and SU(1,1) interferometers 被引量:1
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作者 JUN LIU WENXIAO LIU +3 位作者 SHITAO LI DONG WEI HONG GAO FULI LI 《Photonics Research》 SCIE EI 2017年第6期136-141,共6页
We investigate the sensitivity of the angular rotation measurement with the method of homodyne detection in SU(2) and SU(1,1) interferometers by employing orbital angular momentum(OAM). By combining a coherent beam wi... We investigate the sensitivity of the angular rotation measurement with the method of homodyne detection in SU(2) and SU(1,1) interferometers by employing orbital angular momentum(OAM). By combining a coherent beam with a vacuum beam in an SU(2) interferometer, we get the sensitivity of the angular rotation measurement as 1/(2N^(1/2)l). We can surpass the limit of the angular rotation measurement in an SU(1,1) interferometer by combining a coherent beam with a vacuum beam or a squeezed vacuum beam when the probe beam has OAM. Without injection, the sensitivity can reach 1/(2N^(1/2)l). In addition, by employing another construction of an SU(1,1) interferometer where the pump beam has OAM, with the same injection of an SU(1,1) interferometer, the sensitivity of the angular rotation measurement can be improved by a factor of 2, reaching 1/(4Nl). The results confirm the potential of this technology for precision measurements in angular rotation measurements. 展开更多
关键词 OAM INTERFEROMETERS Enhancement of the angular rotation measurement sensitivity based on SU and SU
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Investigation of stimulated rotational Raman scattering of the high-power broadband laser with applied angular dispersion
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作者 樊心民 吕志伟 +4 位作者 林殿阳 刘颖 朱成禹 何伟明 丁磊 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期276-279,共4页
Smoothing by spectral dispersion (SSD) leads to considerable improvement on laser-irradiation uniformity in far field for fusion lasers. Phase modulation in time and spectral angular dispersion (SAD) across the be... Smoothing by spectral dispersion (SSD) leads to considerable improvement on laser-irradiation uniformity in far field for fusion lasers. Phase modulation in time and spectral angular dispersion (SAD) across the beam introduced by SSD will affect the stimulated rotational Raman scattering (SRRS) gain in the near field. This paper focuses on the influence of SAD on SRRS gain under different laser conditions. Results show that the SAD will aggravate the generation of SRRS when the laser initial additional phase is constant. On the contrary, the SAD can reduce the SRRS gain if appropriate SSD parameters are adopted when the laser initial additional phase is variable. SSD has a certain application prospect in SRRS suppression. 展开更多
关键词 spectral angular dispersion smoothing by spectral dispersion rotational Raman scattering
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Multi-Barycenter Mechanics, N-Body Problem and Rotation of Galaxies and Stars
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作者 Honglai Zhu 《Journal of Applied Mathematics and Physics》 2023年第10期3251-3273,共23页
In the present paper, the establishment of a systematic multi-barycenter mechanics is based on the multi-particle mechanics. The new theory perfects the basic theoretical system of classical mechanics, which finds the... In the present paper, the establishment of a systematic multi-barycenter mechanics is based on the multi-particle mechanics. The new theory perfects the basic theoretical system of classical mechanics, which finds the law of mutual interaction between particle groups, reveals the limitations of Newton’s third law, discovers the principle of the intrinsic relationship between gravity and tidal force, reasonably interprets the origin and change laws for the rotation angular momentum of galaxies and stars and so on. By applying new theory, the multi-body problem can be transformed into a special two-body problem and for which an approximate solution method is proposed, the motion law of each particle can be roughly obtained. 展开更多
关键词 Multi-Barycenter Mechanics Translation Principle for a Vector System Variation Principle for a Vector Origin and Change Laws for the rotation angular Momentum of Galaxies and Stars Multi-Body Problem
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Multichannel singular spectrum analysis of the axial atmospheric angular momentum 被引量:4
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作者 Leonid Zotov N.S.Sidorenkov +2 位作者 Ch.Bizouard C.K.Shum Wenbin Shen 《Geodesy and Geodynamics》 2017年第6期433-442,共10页
Earth's variable rotation is mainly produced by the variability of the AAM(atmospheric angular momentum). In particular, the axial AAM component X_3, which undergoes especially strong variations,induces changes in ... Earth's variable rotation is mainly produced by the variability of the AAM(atmospheric angular momentum). In particular, the axial AAM component X_3, which undergoes especially strong variations,induces changes in the Earth's rotation rate. In this study we analysed maps of regional input into the effective axial AAM from 1948 through 2011 from NCEP/NCAR reanalysis. Global zonal circulation patterns related to the LOD(length of day) were described. We applied MSSA(Multichannel Singular Spectrum Analysis) jointly to the mass and motion components of AAM, which allowed us to extract annual, semiannual, 4-mo nth, quasi-biennial, 5-year, and low-frequency oscillations. PCs(Principal components) strongly related to ENSO(El Nino southern oscillation) were released. They can be used to study ENSO-induced changes in pressure and wind fields and their coupling to LOD. The PCs describing the trends have captured slow atmospheric circulation changes possibly related to climate variability. 展开更多
关键词 Earth's variable rotation Atmospheric circulation AAM(Atmospheric angular momentum) MSSA(Multichannel singular spectrum analysis) ENSO(El Nino southern oscillation) LOD(Length of day)
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Observation and mitigation of image distortion in high-energy electron radiography
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作者 Hao-Qing Li Liang Sheng +22 位作者 Chang-Qing Zhang Ying-Chao Du Zheng Zhou Xiu-Feng Weng Jia-Hao Xiao Hong-Qiao Yin Bin Sun Kun Wei Yang Li Bao-Jun Duan Yong-Tang Liu Yan-Hong Zhang Mei Zhang Yan Song Xiao-Dong Zhang Jun Liu Zhu-Ming Fu Qing Xu Xue Du Jian-Peng Gao Xin-Yi Wang Xin-Jian Tan Dong-Wei Hei 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第6期69-77,共9页
Image distortion caused by the angular misalignment of quadrupole magnets in high-energy electron radiography has been studied systematically.We propose that the distortion originates from the coupling of the electron... Image distortion caused by the angular misalignment of quadrupole magnets in high-energy electron radiography has been studied systematically.We propose that the distortion originates from the coupling of the electron motions in the transverse directions,based on a theoretical analysis and the transfer-matrix method.The relative angular rotation between the second and third magnetic quadrupoles was identified as the main contributor to image distortion.This was verified by both a beam-dynamics simulation and experiments.Different strategies to mitigate this image distortion are also explored,including magnets online tuning,higher beam energy and larger magnification factor.This study provides criteria for designing experiments and paves the way for achieving higher image precision. 展开更多
关键词 MISALIGNMENT angular rotation Russian quadruplet Transfer matrix
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A New Theory on the Origin and Nature of the Fine Structure Constant 被引量:3
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作者 Nader Butto 《Journal of High Energy Physics, Gravitation and Cosmology》 2020年第4期579-589,共11页
The nature and the origin of the fine structure are described. Based on the vortex model and hydrodynamics, a comprehensible interpretation of the fine structure constant is developed. The vacuum considered to have su... The nature and the origin of the fine structure are described. Based on the vortex model and hydrodynamics, a comprehensible interpretation of the fine structure constant is developed. The vacuum considered to have superfluid characteristics and elementary particles such as the electron and Hydrogen molecule are irrotational vortices of this superfluid. In such a vortex, the angular rotation ω is maintained, and the larger the radius, the slower the rotational speed. The fine structure value is derived from the ratio of the rotational speed of the boundaries of the vortex to the speed of the vortex eye in its center. Since the angular rotation is constant, the same value was derived from the ratio between the radius of the constant vortex core and the radius of the hall vortex. Therefore, the constancy of alpha is an expression of the constancy relation in the vortex structure. 展开更多
关键词 Fine Structure Constant angular rotation Irrotational Vortex Vortex Electron Structure Hydrogen Atom Structure
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Application of hybrid robust three-axis attitude control approach to overactuated spacecraft——A quaternion based model 被引量:2
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作者 A.H.Mazinan 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第7期1740-1753,共14页
A novel hybrid robust three-axis attitude control approach, namely HRTAC, is considered along with the well-known developments in the area of space systems, since there is a consensus among the related experts that th... A novel hybrid robust three-axis attitude control approach, namely HRTAC, is considered along with the well-known developments in the area of space systems, since there is a consensus among the related experts that the new insights may be taken into account as decision points to outperform the available materials. It is to note that the traditional control approaches may generally be upgraded, as long as a number of modifications are made with respect to state-of-the-art, in order to propose high-precision outcomes. Regarding the investigated issues, the robust sliding mode finite-time control approach is first designed to handle three-axis angular rates in the inner control loop, which consists of the pulse width pulse frequency modulations in line with the control allocation scheme and the system dynamics. The main subject to employ these modulations that is realizing in association with the control allocation scheme is to be able to handle a class of overactuated systems, in particular. The proportional derivative based linear quadratic regulator approach is then designed to handle three-axis rotational angles in the outer control loop, which consists of the system kinematics that is correspondingly concentrated to deal with the quaternion based model. The utilization of the linear and its nonlinear terms, simultaneously, are taken into real consideration as the research motivation, while the performance results are of the significance as the improved version in comparison with the recent investigated outcomes. Subsequently, there is a stability analysis to verify and guarantee the closed loop system performance in coping with the whole of nominal referenced commands. At the end, the effectiveness of the approach considered here is highlighted in line with a number of potential recent benchmarks. 展开更多
关键词 three-axis angular rates and rotations sliding mode finite-time control approach proportional derivative based linearquadratic regulator approach dynamics and kinematics of overactuated spacecraft
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Stereodynamics of O(^3P)+H2 at Scattering Energies of 0.5, 0.75, and 1.0 eV 被引量:2
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作者 Victor Wei-keh Wu 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第2期149-154,I0001,共7页
Quasiclassical trajectory calculation of the title reaction O(^3P)+H2→OH+H at three different scattering energies of 0.5, 0.75, and 1.0 eV on the lowest electronic potential energy surface 1^3A" has been done. D... Quasiclassical trajectory calculation of the title reaction O(^3P)+H2→OH+H at three different scattering energies of 0.5, 0.75, and 1.0 eV on the lowest electronic potential energy surface 1^3A" has been done. Distribution P(θr) of polar angles between the relative velocityk of the reactant and rotational angular momentum vector j' of the product, distribution P(φr) of the azimuthal as well as dihedral angles correlating k-k'-j', 3-dimensional distri-bution, and polarization-dependent differential cross sections (PDDCSs)dependent upon the scattering angle of the product molecule OH between the relative velocity k of the reactant and k' of the product at different scattering energies of 0.5, 0.75, and 1.0 eV are presented and discussed. 展开更多
关键词 Quasiclassical trajectory calculation Stereodynamics Alignment rotational angular momentum Polarization-dependent differential cross section O+H2 reaction
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Atmospheric and Oceanic Excitations to LOD Change on Quasi-biennial Tune Scales 被引量:1
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作者 Li-Hua Ma De-Chun Liao Yan-Ben Han 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2006年第6期759-768,共10页
We use wavelet transform to study the time series of the Earth's rotation rate (length-of-day, LOD), the axial components of atmospheric angular momentum (AAM) and oceanic angular momentum (OAM) in the period 1... We use wavelet transform to study the time series of the Earth's rotation rate (length-of-day, LOD), the axial components of atmospheric angular momentum (AAM) and oceanic angular momentum (OAM) in the period 1962-2005, and discuss the quasi-biennial oscillations (QBO) of LOD change. The results show that the QBO of LOD change varies remarkably in amplitude and phase. It was weak before 1978, then became much stronger and reached maximum values during the strong El Nino events in around 1983 and 1997. Results from analyzing the axial AAM indicate that the QBO signals in axial AAM are extremely consistent with the QBOs of LOD change. During 1963-2003, the QBO variance in the axial AAM can explain about 99.0% of that of the LOD, in other words, all QBO signals of LOD change are almost excited by the axial AAM, while the weak QBO signals of the axial OAM are quite different from those of the LOD and the axial AAM in both time-dependent characteristics and magnitudes. The combined effects of the axial AAM and OAM can explain about 99.1% of the variance of QBO in LOD change during this period. 展开更多
关键词 Earth's variable rotation - atmospheric angular momentum - oceanic angular momentum
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Application of Novel Rotation Angular Model for 3D Mouse System Based on MEMS Accelerometers
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作者 钱莉 陈文元 徐国平 《Journal of Shanghai Jiaotong university(Science)》 EI 2009年第2期137-142,共6页
A new scheme is proposed to model 3D angular motion of a revolving regular object with miniature, low-cost micro electro mechanical systems(MEMS) accelerometers(instead of gyroscope),which is employed in 3D mouse syst... A new scheme is proposed to model 3D angular motion of a revolving regular object with miniature, low-cost micro electro mechanical systems(MEMS) accelerometers(instead of gyroscope),which is employed in 3D mouse system.To sense 3D angular motion,the static property of MEMS accelerometer,sensitive to gravity acceleration,is exploited.With the three outputs of configured accelerometers,the proposed model is implemented to get the rotary motion of the rigid object.In order to validate the effectiveness of the proposed model,an input device is developed with the configuration of the scheme.Experimental results show that a simulated 3D cube can accurately track the rotation of the input device.The result indicates the feasibility and effectiveness of the proposed model in the 3D mouse system. 展开更多
关键词 micro electro mechanical systems (MEMS) accelerometer 3D mouse rotation angular model homogeneous transformation matrix 3D graphical user interface
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Numerical Study of Vortex Interactions in Bose-Einstein Condensation
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作者 Yanzhi Zhang 《Communications in Computational Physics》 SCIE 2010年第7期327-350,共24页
The dynamics and interaction of quantized vortices in Bose-Einstein condensates(BECs)are investigated by using the two-dimensional Gross-Pitaevskii equation(GPE)with/without an angular momentum rotation term.If all vo... The dynamics and interaction of quantized vortices in Bose-Einstein condensates(BECs)are investigated by using the two-dimensional Gross-Pitaevskii equation(GPE)with/without an angular momentum rotation term.If all vortices have the same winding number,they would rotate around the trap center but never collide.In contrast,if the winding numbers are different,their interaction highly depends on the initial distance between vortex centers.The analytical results are presented to describe the dynamics of the vortex centers when β=0.While if β≠0,there is no analytical result but some conclusive numerical findings are provided for the further understanding of vortex interaction in BECs.Finally,the dynamic laws describing the relation of vortex interaction in nonrotating and rotating BECs are presented. 展开更多
关键词 Rotating Bose-Einstein condensation Gross-Pitaevskii equation angular momentum rotation vortex interaction vortex pair vortex dipole
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