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Unconditionally stable Crank-Nicolson algorithm with enhanced absorption for rotationally symmetric multi-scale problems in anisotropic magnetized plasma
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作者 WEN Yi WANG Junxiang XU Hongbing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期65-73,共9页
Large calculation error can be formed by directly employing the conventional Yee’s grid to curve surfaces.In order to alleviate such condition,unconditionally stable CrankNicolson Douglas-Gunn(CNDG)algorithm with is ... Large calculation error can be formed by directly employing the conventional Yee’s grid to curve surfaces.In order to alleviate such condition,unconditionally stable CrankNicolson Douglas-Gunn(CNDG)algorithm with is proposed for rotationally symmetric multi-scale problems in anisotropic magnetized plasma.Within the CNDG algorithm,an alternative scheme for the simulation of anisotropic plasma is proposed in body-of-revolution domains.Convolutional perfectly matched layer(CPML)formulation is proposed to efficiently solve the open region problems.Numerical example is carried out for the illustration of effectiveness including the efficiency,resources,and absorption.Through the results,it can be concluded that the proposed scheme shows considerable performance during the simulation. 展开更多
关键词 anisotropic magnetized plasma body-of-revolution(BOR) Crank-Nicolson Douglas-Gunn(CNDG) finite-difference time-domain(FDTD) perfectly matched layer(PML) rotationally symmetric multi-scale problems
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Predictive factors for photic phenomena after refractive,rotationally asymmetric,multifocal intraocular lens implantation 被引量:16
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作者 Hungwon Tchah Kiyeun Nam Aeri Yoo 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第2期241-245,共5页
AIM: To investigate the independent factors associated with photic phenomena in patients implanted with refractive,rotationally asymmetric,multifocal intraocular lenses(MIOLs).METHODS: Thirty-four eyes of 34 patie... AIM: To investigate the independent factors associated with photic phenomena in patients implanted with refractive,rotationally asymmetric,multifocal intraocular lenses(MIOLs).METHODS: Thirty-four eyes of 34 patients who underwent unilateral cataract surgery,followed by implantation of rotationally asymmetric MIOLs were included.Distance and near visual acuity outcomes,intraocular aberrations,preferred reading distances,preoperative and postoperative refractive errors,mesopic and photopic pupil diameters,and the mesopic and photopic kappa angles were assessed.Patients were also administered a satisfaction survey.Photic phenomena were graded by questionnaire.Independent-related factors were identified by correlation and bivariate logistic regression analyses.RESULTS: The distance from the photopic to the mesopic pupil center(pupil center shift) was significantly associated with glare/halo symptoms [odds ratio(OR)=2.065,95% confidence interval(CI)=0.916-4.679,P=0.006] and night vision problems(OR=1.832,95% CI=0.721-2.158,P=0.007).The preoperative photopic angle kappa was significantly associated with glare/halo symptoms(OR=2.155,95% CI=1.065-4.362,P=0.041).The photopic angle kappa was also significantly associated with glare/halo symptoms(OR=2.155,95% CI=1.065-4.362,P=0.041) and with night vision problems(OR=1.832,95% CI=0.721-2.158,P=0.007) in patients implanted with rotationally asymmetric MIOLs.CONCLUSION: A large pupil center shift and misalignment between the visual and pupillary axis(angle kappa)may play a role in the occurrence of photic phenomena after implantation of rotationally asymmetric MIOLs. 展开更多
关键词 rotationally asymmetric multifocal intraocular lens pupil center photic phenomena dysphotopsia kappa angle pupil center shift
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Computer Assisted Assignments of Rotationally Resolved Molecular Spectra 被引量:1
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作者 Ling Wu Li-juan Zheng +2 位作者 Xiao-hua Yang Yu-yan Liu Yang-qin Chena 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第1期39-42,共4页
A graphically oriented interactive program for assignments of rotationally resolved molecular spectra has been devised. The program functions by grouping spectral lines in term of the second difference principle. and ... A graphically oriented interactive program for assignments of rotationally resolved molecular spectra has been devised. The program functions by grouping spectral lines in term of the second difference principle. and graphing spectral intensity versus frequency in a bar graph of the selected groups, distinguished by color and/or line-type. This allows for easy detection of regular patterns buried in the observed spectrum. Furthermore, it includes a Loomis-Wood view for assisting in spectral assignments. As an example, the program was applied in assigning the molecular spectrum of the production in the discharge of PCl3 buffered by helium gas, which may belong to several species. The results suggest that the program is highly efficient and quite useful in the assignment and the analysis of molecular spectra, especially those of symmetric top, slightly asymmetric top and linear molecules. The accuracy and efficiency of this program will likely ensure its wide application in the processing of molecular spectra. 展开更多
关键词 ASSIGNMENT rotationally resolved Molecular spectra Computer assisted
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Method for compensating translational motion of rotationally symmetric target based on local symmetry cancellation 被引量:1
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作者 Jingqing Li Sisan He +1 位作者 Cunqian Feng Yizhe Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第1期36-39,共4页
The micro-Doppler effect of moving targets may suffer from aliasing and Doppler migration due to the translational motion, which affects the application in real-time target identification. A new compensating method fo... The micro-Doppler effect of moving targets may suffer from aliasing and Doppler migration due to the translational motion, which affects the application in real-time target identification. A new compensating method for the rotationally symmetric target is proposed and demonstrated. By utilizing the micro-Doppler symmetry cancellation effect, the method can accurately compensate the translation effect, meanwhile, it behaves well in noise restraint. Computer simulations verify the high accuracy and efficiency of this method. 展开更多
关键词 target recognition rotationally symmetric micro Doppler translation compensation.
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Comparative analysis of visual quality between unilateral implantation of a trifocal intraocular lens and a rotationally asymmetric refractive multifocal intraocular lens 被引量:1
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作者 Na Hui Mei-Fang Chu +3 位作者 Yan Li Cong-Yi Wang Lei Yu Bo Ma 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2022年第9期1460-1467,共8页
·AIM:To compare visual quality after unilateral cataract surgery with implantation of trifocal intraocular lens(IOL)and asymmetric refractive multifocal IOL.·METHODS:The prospective nonrandom,comparative stu... ·AIM:To compare visual quality after unilateral cataract surgery with implantation of trifocal intraocular lens(IOL)and asymmetric refractive multifocal IOL.·METHODS:The prospective nonrandom,comparative study consisted of 60 eyes of 60 patients suffering unilateral cataract surgery with implantation of two different IOLs:AT LISA tri 839 MP(30 eyes;Carl Zeiss Meditec,Germany)and LS-313 MF30(30 eyes;Oculentis GmbH,Germany).Visual acuity,refractive outcome,contrast sensitivity,defocus curves,quality of vision,and optical phenomena were evaluated at3 mo postoperatively.·RESULTS:There were no statistical differences between groups in uncorrected distance visual acuity(P=0.13)and uncorrected near visual acuity(P=0.54).In contrast,uncorrected intermediate visual acuity was better in trifocal group compared to the refractive multifocal group(P=0.02).No significant statistical between-group difference was detected in cylinder(P=0.43).Compared to trifocal group,spherical refraction and spherical equivalent in refractive multi focal group were more myopic(P<0.01).Under photopic conditions,no significant statistical differences were found between groups in contrast sensitivity at 3 and 6 cycles per degree(cpd).The refractive multifocal group performed better at 12 and 18 cpd than the trifocal group(P=0.01,P=0.034,respectively).The questionnaires of quality of vision and optical phenomena showed no differences between groups.·CONCLUSION:Trifocal IOL is superior to refractive multifocal IOL in intermediate visual acuity.Rotationally asymmetric refractive multifocal IOL is more myopic in automated refraction and significantly better for the photopic contrast sensitivity at high frequency. 展开更多
关键词 trifocal intraocular lens rotationally asymmetric multifocal intraocular lens visual quality contrast sensitivity
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ON SOME ROTATIONALLY SYMMETRIC GRADIENT PSEUDO-KHLER-RICCI SOLITONS
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作者 段孝娟 《Acta Mathematica Scientia》 SCIE CSCD 2018年第1期269-288,共20页
In this paper, we explicitly construct some rotationally symmetric gradient pseudo- Kahler-Ricci solitons which depend on some parameters, on some line bundles and other bundles over projective spaces. We also discuss... In this paper, we explicitly construct some rotationally symmetric gradient pseudo- Kahler-Ricci solitons which depend on some parameters, on some line bundles and other bundles over projective spaces. We also discuss the "phase change" phenomenon caused by the variation of parameters. 展开更多
关键词 pseudo-Kahler-Ricci soliton rotationally symmetric phase change gradient soliton
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Secondary positioning of rotationally asymmetric refractive multifocal intraocular lens in a patient with glaucoma:A case report
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作者 Cong Fan Yi Zhou Jian Jiang 《World Journal of Clinical Cases》 SCIE 2022年第20期7013-7019,共7页
BACKGROUND Asymmetric multifocal intraocular lenses(IOLs)are now widely used in the modern cataract surgery,providing a good level of visual performance over a range of distances and high postoperative patient satisfa... BACKGROUND Asymmetric multifocal intraocular lenses(IOLs)are now widely used in the modern cataract surgery,providing a good level of visual performance over a range of distances and high postoperative patient satisfaction.We report a case of improved visual quality after shifting the near segment of an asymmetrical multifocal IOL to the superotemporal placement in the dominant eye of a glaucoma patient.CASE SUMMARY A 72-year-old woman with bilateral glaucoma underwent phacoemulsification in the dominant eye(left eye)with implantation of an asymmetrical multifocal IOL.Postoperative uncorrected distance visual acuity(UDVA)was 0.0 logMAR(20/20 Snellen)and uncorrected near visual acuity(UNVA)was 0.1 logMAR(20/25 Snellen).Two weeks later,the patient presented to our clinic with decreased vision due to migration of lens epithelial cells to IOL anterior surface and edema of corneal endothelial cells.Anterior capsule polishing and superotemporal placement of near segment[+3.00 diopter(D)addition(add)]of IOL were performed.As a result,UDVA at the first week and first year after reposition was 0.0 logMAR(20/20 Snellen),and compared with 0.3 logMAR(20/40 Snellen)in the first week,the UNVA was improved to 0.0 logMAR(20/20 Snellen)one year after surgery.CONCLUSION The postoperative inflammatory reaction and lens epithelial cells proliferation were obvious in this glaucoma patient.Capsule polishing and rotation of the lens were beneficial to the patient,which not only enhanced the patient's vision,but also improved the patient's satisfaction.Therefore,glaucoma patients need to be cautious of implanting multifocal IOLs.Placement of a near segment of an asymmetrical multifocal IOL in the dominant eye should be performed on an individual basis. 展开更多
关键词 Cataract surgery GLAUCOMA rotationally asymmetric refractive multifocal intraocular lens Visual quality Patient satisfaction Case report
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THE ROTATIONALLY PERIODIC SYMMETRY IN BEM
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作者 Yang Haitian (Department of Engineering Mechanics,Dalian University of Technology,P.R.China)Wu Gaofeng Wu Jingning (Research Institute of Engineering Mechanics,Dalian University of Technology,P.R.China) 《Acta Mechanica Solida Sinica》 SCIE EI 1994年第3期235-244,共10页
Rotationally periodic symmetry is exploited in 2-D elastostatic calculation using the BEM.It is proved that the coefficient matrices of the global boundary element equations for the rotationally periodic system are bl... Rotationally periodic symmetry is exploited in 2-D elastostatic calculation using the BEM.It is proved that the coefficient matrices of the global boundary element equations for the rotationally periodic system are block-circulant so long as a kind of symmetry-adapted reference coordinate system is adopted. Furthermore,an efficient algorithm,which partitions the original problem of solving the boundary element equations into a series of subproblems,is proposed.The method permits arbitrary load distribution for stress analysis problems. 展开更多
关键词 rotationally periodic symmetry boundary element
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NUMERICAL ANALYSIS OF BIFURCATION BUCKLING FOR ROTATIONALLY PERIODIC STRUCTURES UNDER ROTATIONALLY PERIODIC LOADS
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作者 李建中 刘应华 +1 位作者 岑章志 徐秉业 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1998年第1期53-64,共12页
By considering the characteristics of deformation of rotationally periodic structures under rotationally periodic loads, the periodic structure is divided into some identical substructures in this study. The degrees-o... By considering the characteristics of deformation of rotationally periodic structures under rotationally periodic loads, the periodic structure is divided into some identical substructures in this study. The degrees-of-freedom (DOFs) of joint nodes between the neighboring substructures are classified as master and slave ones. The stress and strain conditions of the whole structure are obtained by solving the elastic static equations for only one substructure by introducing the displacement constraints between master and slave DOFs. The complex constraint method is used to get the bifurcation buckling load and mode for the whole rotationally periodic structure by solving the eigenvalue problem for only one substructure without introducing any additional approximation. The finite element (FE) formulation of shell element of relative degrees of freedom (SERDF) in the buckling analysis is derived. Different measures of tackling internal degrees of freedom for different kinds of buckling problems and different stages of numerical analysis are presented. Some numerical examples are given to illustrate the high efficiency and validity of this method. 展开更多
关键词 rotationally periodic structure bifurcation buckling complex constraint method SUBSTRUCTURE shell element of relative degrees of freedom(SERDF)
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Effect of interaction of the various modes on the radial velocity curves of the polytropic models of rotationally and tidally distorted pulsating variable stars
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作者 Tarun Kumar Ankush Pathania Arvind Kumar Lal 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第12期53-66,共14页
In our previous work, we developed a model to study the effects of rotation and/or tidal distortions on anharmonic radial oscillations and hence on the radial velocity curves of the polytropic models of pulsating vari... In our previous work, we developed a model to study the effects of rotation and/or tidal distortions on anharmonic radial oscillations and hence on the radial velocity curves of the polytropic models of pulsating variable stars.We considered the first three modes(fundamental and the next two higher modes) for the polytropic models of index 1.5 and 3.0 in that work.In the present paper, we are further extending our previous work to study the effect of the interaction of various modes on anharmonic radial oscillations and hence on radial velocity curves of the rotationally and/or tidally distorted polytropic models of pulsating variable stars.For this purpose, we have considered the following cases:(i) fundamental mode(ii) fundamental and the first mode,(iii) fundamental and the next two modes and finally(iv) fundamental and the next three higher modes of pulsation in our study.The objective of this paper is also to investigate whether the interaction of various modes affects the results of our previous study or not.The results of this study show that the interaction of the fundamental mode with higher modes appreciably changes the shape of the radial velocity curve of rotationally distorted and rotationally and tidally distorted polytropic models of pulsating variable stars. 展开更多
关键词 stars:rotation stars:oscillations stars:binaries technique:radial velocities
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Effect of rotationally accelerated shot peening on the microstructure and mechanical behavior of a metastableβtitanium alloy 被引量:5
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作者 Xinkai Ma Zhuo Chen +4 位作者 Dongling Zhong SNLuo Lei Xiao Wenjie Lu Shanglin Zhang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第16期27-38,共12页
Microstructural evolution and deformation mechanism of a metastableβalloy(Ti-10 V-2 Fe-3 Al)processed by rotationally accelerated shot peening(RASP)were systematically investigated with optical microscopy,X-ray diffr... Microstructural evolution and deformation mechanism of a metastableβalloy(Ti-10 V-2 Fe-3 Al)processed by rotationally accelerated shot peening(RASP)were systematically investigated with optical microscopy,X-ray diffraction,electron backscatter diffraction and transmission electron microscopy.Different gradient hierarchical microstructures(gradients inα″martensite andβphase,and hierarchical twins range from the nanoscale to microscale)can be fabricated by RASP via changing the shot peening time.The hardening behavior and tensile mechanical properties of gradient hierarchical microstructure were systematically explored.Novel deformation twinning systems of{112}α″and{130}<310>α″in the kinkedα″martensite were revealed during the tensile deformation.It was found that stress-induced martensitic transformation,twinnedα″martensite and the related dynamic grain refinement contribute to hardness and work hardening ability.Simultaneous improvement of strength and ductility of the metastableα″titanium alloy can be achieved by introducing a gradient hierarchical microstructure. 展开更多
关键词 Titanium alloys Gradient hierarchical microstructure α″martensite rotationally accelerated shot peening Mechanical behavior
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VANISHING OF THREE-DIMENSIONALITY IN THE WAKE BEHIND A ROTATIONALLY OSCILLATING CIRCULAR CYLINDER 被引量:5
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作者 DENG Jian SHAO Xue-ming REN An-lu 《Journal of Hydrodynamics》 SCIE EI CSCD 2007年第6期751-755,共5页
The flow behind a three-dimensional rotationally oscillating circular cylinder was studied by a numerical method. The computations were performed at a Reynolds number of 260, which is at a level that the flow wake has... The flow behind a three-dimensional rotationally oscillating circular cylinder was studied by a numerical method. The computations were performed at a Reynolds number of 260, which is at a level that the flow wake has developed into a three-dimensional state called Mode-B. The purpose of this paper is to examine the influence of various rotational amplitudes (0.1-0.7) on the wake instability of the flow, while the oscillation frequency is fixed to the value of that measured in the wake of a stationary cylinder. The results show that the rotation with sufficiently high amplitude brings the flow back to its nominal two-dimensional state. Moreover, it is found that the value of the time-averaged drag and the RMS value of the lift are larger than those of a stationary circular cylinder. 展开更多
关键词 rotationally oscillating circular cylinder wake instability oscillation frequency
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Gradient Structured Copper by Rotationally Accelerated Shot Peening 被引量:17
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作者 X.Wang Y.S.Li +2 位作者 Q.Z.ang Y.H.Zhao Y.T.Zhu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2017年第7期758-761,共4页
A new technology-rotationally accelerated shot peening(RASP), was developed to prepare gradient structured materials. By using centrifugal acceleration principle and large steel balls, the RASP technology can produc... A new technology-rotationally accelerated shot peening(RASP), was developed to prepare gradient structured materials. By using centrifugal acceleration principle and large steel balls, the RASP technology can produce much higher impact energy compared to conventional shot peening. As a proof-of-concept demonstration, the RASP was utilized to refine the surface layer in pure copper(Cu) with an average grain size of 85 nm. The grain size increases largely from surface downwards the bulk, forming an800 ?m thick gradient-structured surface layer and consequently a micro-hardness gradient. The difference between the RASP technology and other established techniques in preparing gradient structured materials is discussed. The RASP technology exhibits a promoting future for large-scale manufacturing of gradient materials. 展开更多
关键词 Microstructure rotationally accelerated shot peening Gradient structure Hardness Copper
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Rotationally symmetric pseudo-Khler metrics of constant scalar curvatures 被引量:2
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作者 DUAN XiaoJuan ZHOU Jian 《Science China Mathematics》 SCIE 2011年第5期925-938,共14页
We study the ordinary differential equations related to rotationally symmetric pseudo-Khler metricsof constant scalar curvatures. We present various solutions on various holomorphic line bundles over projectivespaces ... We study the ordinary differential equations related to rotationally symmetric pseudo-Khler metricsof constant scalar curvatures. We present various solutions on various holomorphic line bundles over projectivespaces and their disc bundles, and discuss the phase change phenomenon when one suitably changes initialvalues. 展开更多
关键词 pseudo-Kahler metrics rotationally symmetric constant scalar curvature phase change
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Rotationally Symmetric Translating Solutions to Curvature Flows in Image Processing
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作者 刘庆华 陈秀卿 《Tsinghua Science and Technology》 SCIE EI CAS 2005年第3期404-407,共4页
This paper proves the existence of rotationally symmetric solutions to a curvature flow in image processing. The flow includes the level sets flow and the mean curvature flow projected onto the normal. Sharp estimates... This paper proves the existence of rotationally symmetric solutions to a curvature flow in image processing. The flow includes the level sets flow and the mean curvature flow projected onto the normal. Sharp estimates are obtained for these solutions.. 展开更多
关键词 level sets flow mean curvature flow singular ordinary differential equation priori estimate rotationally symmetry
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A modified stochastic model for LS+AR hybrid method and its application in polar motion short-term prediction 被引量:1
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作者 Fei Ye Yunbin Yuan 《Geodesy and Geodynamics》 EI CSCD 2024年第1期100-105,共6页
Short-term(up to 30 days)predictions of Earth Rotation Parameters(ERPs)such as Polar Motion(PM:PMX and PMY)play an essential role in real-time applications related to high-precision reference frame conversion.Currentl... Short-term(up to 30 days)predictions of Earth Rotation Parameters(ERPs)such as Polar Motion(PM:PMX and PMY)play an essential role in real-time applications related to high-precision reference frame conversion.Currently,least squares(LS)+auto-regressive(AR)hybrid method is one of the main techniques of PM prediction.Besides,the weighted LS+AR hybrid method performs well for PM short-term prediction.However,the corresponding covariance information of LS fitting residuals deserves further exploration in the AR model.In this study,we have derived a modified stochastic model for the LS+AR hybrid method,namely the weighted LS+weighted AR hybrid method.By using the PM data products of IERS EOP 14 C04,the numerical results indicate that for PM short-term forecasting,the proposed weighted LS+weighted AR hybrid method shows an advantage over both the LS+AR hybrid method and the weighted LS+AR hybrid method.Compared to the mean absolute errors(MAEs)of PMX/PMY sho rt-term prediction of the LS+AR hybrid method and the weighted LS+AR hybrid method,the weighted LS+weighted AR hybrid method shows average improvements of 6.61%/12.08%and 0.24%/11.65%,respectively.Besides,for the slopes of the linear regression lines fitted to the errors of each method,the growth of the prediction error of the proposed method is slower than that of the other two methods. 展开更多
关键词 Stochastic model LS+AR Short-term prediction The earth rotation parameter(ERP) Observation model
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Linear and Non-Linear Dynamics of Inertial Waves in a Rotating Cylinder with Antiparallel Inclined Ends 被引量:1
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作者 Mariya Shiryaeva Mariya Subbotina Stanislav Subbotin 《Fluid Dynamics & Materials Processing》 EI 2024年第4期787-802,共16页
This work is devoted to the experimental study of inertial wave regimes in a non-uniform rotating cylinder with antiparallel inclined ends.In this setting,the cross-section of the cylinder is divided into two regions ... This work is devoted to the experimental study of inertial wave regimes in a non-uniform rotating cylinder with antiparallel inclined ends.In this setting,the cross-section of the cylinder is divided into two regions where the fluid depth increases or decreases with radius.Three different regimes are found:inertial wave attractor,global oscillations(the cavity’s resonant modes)and regime of symmetric reflection of wave beams.In linear wave regimes,a steady single vortex elongated along the rotation axis is generated.The location of the wave’s interaction with the sloping ends determines the vortex position and the vorticity sign.In non-linear regimes several pairs of the triadic resonance subharmonics are detected simultaneously.The instability of triadic resonance is accompanied by the periodic generation of mean vortices drifting in the azimuthal direction.Moreover,the appearance frequency of the vortices is consistent with the low-frequency subharmonic of the triadic resonance.The experimental results shed light on the mechanisms of the inertial wave interaction with zonal flow and may be useful for the development of new methods of mixing. 展开更多
关键词 ROTATION inertial wave attractor triadic resonance zonal flow instability
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Nitrogen rhizodeposition from corn and soybean,and its contribution to the subsequent wheat crops
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作者 Sainan Geng Lantao Li +6 位作者 Yuhong Miao Yinjie Zhang Xiaona Yu Duo Zhang Qirui Yang Xiao Zhang Yilun Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2446-2457,共12页
Nitrogen(N)is a key factor in the positive response of cereal crops that follow leguminous crops when compared to gramineous crops in rotations,with the nonrecyclable rhizosphere-derived N playing an important role.Ho... Nitrogen(N)is a key factor in the positive response of cereal crops that follow leguminous crops when compared to gramineous crops in rotations,with the nonrecyclable rhizosphere-derived N playing an important role.However,quantitative assessments of differences in the N derived from rhizodeposition(NdfR)between legumes and gramineous crops are lacking,and comparative studies on their contributions to the subsequent cereals are scarce.In this study,we conducted a meta-analysis of NdfR from leguminous and gramineous crops based on 34 observations published worldwide.In addition,pot experiments were conducted to study the differences in the NdfR amounts,distributions and subsequent effects of two major wheat(Triticum aestivum L.)-preceding crops,corn(Zea mays L.)and soybean(Glycine max L.),by the cotton wick-labelling method in the main wheat-producing areas of China.The meta-analysis results showed that the NdfR of legumes was significantly greater by 138.93%compared to gramineous crops.In our pot experiment,the NdfR values from corn and soybean were 502.32 and 944.12 mg/pot,respectively,and soybean was also significantly higher than corn,accounting for 76.91 and 84.15%of the total belowground nitrogen of the plants,respectively.Moreover,in different soil particle sizes,NdfR was mainly enriched in the large macro-aggregates(>2 mm),followed by the small macro-aggregates(2–0.25 mm).The amount and proportion of NdfR in the macro-aggregates(>0.25 mm)of soybean were 3.48 and 1.66 times higher than those of corn,respectively,indicating the high utilization potential of soybean NdfR.Regarding the N accumulation of subsequent wheat,the contribution of soybean NdfR to wheat was approximately 3 times that of corn,accounting for 8.37 and 4.04%of the total N uptake of wheat,respectively.In conclusion,soybean NdfR is superior to corn in terms of the quantity and distribution ratio of soil macro-aggregates.In future field production,legume NdfR should be included in the nitrogen pool that can be absorbed and utilized by subsequent crops,and the role and potential of leguminous plants as nitrogen source providers in crop rotation systems should be fully utilized. 展开更多
关键词 crop rotation nitrogen rhizodeposition meta-analysis soil aggregates nitrogen transfer
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Magnetic Interactions with Strain Gradient in Ultrathin Pr_(0.67)Sr_(0.33)MnO_(3) Films
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作者 Bangmin Zhang Ping Yang +2 位作者 Jun Ding Jingsheng Chen Gan Moog Chow 《Engineering》 SCIE EI CAS CSCD 2024年第9期158-165,共8页
Strain gradient is a normal phenomenon around a heterostructural interface in ultrathin film,and it is important to determine its effect on magnetic interactions to understand interfacial coupling.In this work,ultrath... Strain gradient is a normal phenomenon around a heterostructural interface in ultrathin film,and it is important to determine its effect on magnetic interactions to understand interfacial coupling.In this work,ultrathin Pr_(0.67)Sr_(0.33)MnO_(3)(PSMO)films on different substrates are studied.For PSMO film under different in-plane strain conditions,the saturated magnetization and Curie temperature can be qualitatively explained by double-exchange interaction and the Jahn-Teller distortion.However,the difference in the saturated magnetization with zero field cooling and 5 T field cooling is proportional to the strain gradient.Strain-gradient-induced structural disorder is proposed to enhance phonon-electron antiferromagnetic interactions and the corresponding antiferromagnetic-to-ferromagnetic phase transition via a strong magnetic field during the field cooling process.A non-monotonous structural transition of the MnO_(6) octahedral rotation can enlarge the strain gradient in PSMO film on a SrTiO_(3) substrate.This work demonstrates the existence of the flexomagnetic effect in ultrathin manganite film,which should be applicable to other complex oxide systems. 展开更多
关键词 Strain gradient Manganite film Octahedral rotation Flexomagnetic Magnetic interactions Phase transition
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A new method for deriving broad-band polar motion geodetic excitations
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作者 Wei Chen Jiesi Luo +1 位作者 Jim Ray Jiancheng Li 《Geodesy and Geodynamics》 EI CSCD 2024年第5期453-464,共12页
While the geodetic excitationχ(t)of polar motion p(t)is essential to improve our understanding of global mass redistributions and relative motions with respect to the terrestrial frame,the widely adopted method to de... While the geodetic excitationχ(t)of polar motion p(t)is essential to improve our understanding of global mass redistributions and relative motions with respect to the terrestrial frame,the widely adopted method to deriveχ(t)from p(t)has biases in both amplitude and phase responses.This study has developed a new simple but more accurate method based on the combination of the frequency-and time-domain Liouville's equation(FTLE).The FTLE method has been validated not only with 6-h sampled synthetic excitation series but also with daily and 6-h sampled polar motion measurements as well asχ(t)produced by the interactive webpage tool of the International Earth Rotation and Reference Systems Service(IERS).Numerical comparisons demonstrate thatχ(t)derived from the FTLE method has superior performances in both the time and frequency domains with respect to that obtained from the widely adopted method or the IERS webpage tool,provided that the input p(t)series has a length around or more than 25 years,which presents no practical limitations since the necessary polar motion data are readily available.The FTLE code is provided in the form of Mat Lab function. 展开更多
关键词 Earth rotation Polar motion Geodetic excitation Liouville's equation Mat Lab
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