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Differential Interference Angle of Collision-induced Rotational Energy Transfer in Na_2(A^1∑_u^+,v=8-b^3∏_(0u),v=14)-Na System
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作者 李健 李永庆 +1 位作者 王伟丽 马凤才 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第6期469-472,共4页
Here wc report calculation of the differential interference angles (including b≤p gild b≥p ) for singlet-triplet mixed states of Na2(A^1∑u^+,ν=8-b^3∏0u,ν=14) system in collision with Na, in order to study t... Here wc report calculation of the differential interference angles (including b≤p gild b≥p ) for singlet-triplet mixed states of Na2(A^1∑u^+,ν=8-b^3∏0u,ν=14) system in collision with Na, in order to study the collision- induced quantum interference on rotational energy transfer in an atom-diatom system. The calculation is based on the first-order Born approximation of time-dependent perturbation theory, and the anisotropic Lennard-Jones intcraction potentials are also employed, The relationships between differential interference angle and impact parameter, including collision diameter and velocity, are obtained, 展开更多
关键词 rotational energy transfer Collision induced quantum interference Interference angle
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Collisional quantum interference on rotational energy transfer: physical interpretation of the differential interference angle 被引量:1
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作者 李永庆 李健 马凤才 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第12期2920-2927,共8页
Collisional quantum interference (CQI) on the intramolecular rotational energy transfer is observed in an experiment with a static cell, and the integral interference angles are measured. To obtain more accurate inf... Collisional quantum interference (CQI) on the intramolecular rotational energy transfer is observed in an experiment with a static cell, and the integral interference angles are measured. To obtain more accurate information, an experiment with a molecular beam is carried out, and thereby the relationship between the differential interference angle and the scattering angle is obtained. Based on the first-Born approximation of time-dependent perturbation theory, the theoretical model of CQI is developed in an atom-diatom system in the condition of the molecular beam, with the long-range interaction potential taken into account. The method of measuring correctly the differential interference angle is presented. The tendencies of the differential interference angle changing with the impact parameter and rel- ative velocity are discussed. The theoretical model presented here is important for understanding or performing the experiment in the molecular beam. 展开更多
关键词 collisional quantum interference rotational energy transfer interference angle longrange interaction potential
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The differential interference angle of ~2Π [Case(a)] diatom on rotational energy transfer in NO (X^2Π ) collision with He,Ne and Ar system 被引量:1
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作者 李永庆 李健 +2 位作者 赵丽娜 倪艳清 马凤才 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第10期3649-3654,共6页
To study theoretically the relationship between the differential interference angle and the scattering angle in collisional quantum interference (CQI), we have investigated the differential interference angle of the... To study theoretically the relationship between the differential interference angle and the scattering angle in collisional quantum interference (CQI), we have investigated the differential interference angle of the atom-diatomic [case(a)] molecule system in detail. For the 2∏ electronic state in Hund's case (a), the degree of the differential interference is also discussed. The differential interference angles of NO(X^2∏) are calculated quantitatively for the rotational energy transfer in Hund's case (a) induced by collision with He, Ne and Ar atoms. The method to calculate the differential interference angle is presented. Several factors that affect the differential interference angle are investigated. Finally the variation of the differential interference angle with the impact parameter and relative velocity is discussed. 展开更多
关键词 collisional quantum interference rotational energy transfer interference angle longrange interaction potential
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The differential interference angle in collisional quantum interference on rotational energy transfer 被引量:1
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作者 王伟丽 苗刚 +2 位作者 陈跃辉 唐丹 马凤才 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第6期2078-2084,共7页
Collisional quantum interference (CQI) in the intramolecular rotational energy transfer was observed in experiment by Sha and co-workers. The interference angle, which measuring the degree of the coherence, were mea... Collisional quantum interference (CQI) in the intramolecular rotational energy transfer was observed in experiment by Sha and co-workers. The interference angle, which measuring the degree of the coherence, were measured in the experiment of the static cell. Based on the first Born approximation of time dependent perturbation theory, taking into accounts the anisotropic Lennard-Jones interaction potentials, this paper describes the theoretical model of CQI in intramolecular rotational energy transfer in an atom-diatom collision system. In the model, the differential interference angle for the experiment of the molecular beam is calculated, the changing tendencies of the differential interference angle with the impact parameter and collision partners are obtained. This theoretical model is important for understanding or performing this kind of experiments. 展开更多
关键词 rotational energy transfer differential interference angle collision parameter
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A Hybrid Conjugate Gradient Algorithm for Solving Relative Orientation of Big Rotation Angle Stereo Pair 被引量:3
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作者 Jiatian LI Congcong WANG +5 位作者 Chenglin JIA Yiru NIU Yu WANG Wenjing ZHANG Huajing WU Jian LI 《Journal of Geodesy and Geoinformation Science》 2020年第2期62-70,共9页
The fast convergence without initial value dependence is the key to solving large angle relative orientation.Therefore,a hybrid conjugate gradient algorithm is proposed in this paper.The concrete process is:①stochast... The fast convergence without initial value dependence is the key to solving large angle relative orientation.Therefore,a hybrid conjugate gradient algorithm is proposed in this paper.The concrete process is:①stochastic hill climbing(SHC)algorithm is used to make a random disturbance to the given initial value of the relative orientation element,and the new value to guarantee the optimization direction is generated.②In local optimization,a super-linear convergent conjugate gradient method is used to replace the steepest descent method in relative orientation to improve its convergence rate.③The global convergence condition is that the calculation error is less than the prescribed limit error.The comparison experiment shows that the method proposed in this paper is independent of the initial value,and has higher accuracy and fewer iterations. 展开更多
关键词 relative orientation big rotation angle global convergence stochastic hill climbing conjugate gradient algorithm
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Distribution of Facial Exposure to Non-melanoma Biologically Effective UV Irradiance Changes by Rotation Angles
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作者 WANG Fang YU Jia Ming +3 位作者 YANG De Qi GAO Qian HUA Hui LIU Yang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2017年第2期113-127,共15页
Objective To show the distribution of facial exposure to non-melanoma biologically effective UV irradiance changes by rotation angles. Methods This study selected the cheek, nose, and forehead as representative facial... Objective To show the distribution of facial exposure to non-melanoma biologically effective UV irradiance changes by rotation angles. Methods This study selected the cheek, nose, and forehead as representative facial sites for UV irradiance measurements, which were performed using a rotating manikin and a spectroradiometer. The measured UV irradiance was weighted using action spectra to calculate the biologically effective UV irradiances that cause non-melanoma (UVBEnon.rnel) skin cancer. The biologically effective UV radiant exposure (HBEnon-mel) was calculated by summing the UVBEnon-mel data collected over the exposure period. Results This study revealed the following: (1) the maximum cheek, nose and forehead exposure UVA and UVB irradiance times and solar elevation angles (SEA) differed from those of the ambient UV irradiance and were influenced by the rotation angles; (2) the UV irradiance exposure increased in the following order: cheek 〈 nose 〈 forehead; (3) the distribution of UVBEnon-mel irradiance differed from that of unweighted UV radiation (UVR) and was influenced by the rotation angles and exposure times; and (4) the maximum percentage decreases in the UVBEnon-melradiant exposure for the cheek, nose and forehead from 0° to 180° were 48.41%, 69.48% and 71.71%, respectively. Conclusion Rotation angles relative to the sun influence the face's exposure to non-melanoma biologically effective UV. 展开更多
关键词 FACIAL Non-melanoma Biologically effective UV rotation angles
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Design of the Rotation Angle Measurement System for the Atmospheric Dispersion Corrector (ADC)
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作者 Wenjie Li Quanquan Mu +4 位作者 Shaoxin Wang Chengliang Yang Haiping Wang Zhaoliang Cao Li Xuan 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2017年第4期57-61,共5页
In order to measure the rotation angle error of the worm and gear mechanisms in the atmospheric dispersion corrector( ADC),a novel measurement system based on the autocollimator is designed in this paper.Based on the ... In order to measure the rotation angle error of the worm and gear mechanisms in the atmospheric dispersion corrector( ADC),a novel measurement system based on the autocollimator is designed in this paper.Based on the position relations between the shaft and spot converged by rays of autocollimator,the rotation angle can be calculated quickly and conveniently using a brief algorithm. An optical wedge is introduced to the measurement system for suppressing the awful measuring error caused by the axial wobbly error. The measurement system can measure the shaft rotation angle at any rotation position,which is the novel usage of the two-dimensional autocollimator. Its optical layout is very simple. Only an optical wedge and two plane mirrors are needed besides the autocollimator. The measurement accuracy of the proposed method is less than±0.5 arcmin. In the measurement of two worms and gears mechanisms in ADC,the rotation angle error are±0.05° and ±0.07° respectively,which all satisfies the design demand( ±0.1°). The proposed measurement system can be also suits for some engineering fields. 展开更多
关键词 OPTICAL measurement rotation angle AUTOCOLLIMATOR AXIS wobbly error OPTICAL WEDGE
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Interference Angle on Quantum Rotational Energy Transfer in Na+Na_2 (A^1Σ_u^+,v = 8~b^3Π_(Ou), v = 14) Molecular Collision System
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作者 WANG Wei-Li MIAO Gang +1 位作者 LI Jian MA Feng-Cai 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第12期1062-1066,共5页
In order to study the collisional quantum interference (CQI) on rotational energy transfer in atom-diatom system, we have studied the relation of the integral interference angle and differential interference angle i... In order to study the collisional quantum interference (CQI) on rotational energy transfer in atom-diatom system, we have studied the relation of the integral interference angle and differential interference angle in Naq-Na2 (A1 ∑u^+,v=8-b^3∏0u,v=14) collision system. In this paper, based on the first-Born approximation of timedependent perturbation theory and taking into accounts the anisotropic effect of Lennard-Jones interaction potentials, we present a theoretical model of collisional quantum interference in intramolecular rotational energy transfer, and a relationship between differential and integral interference angles. 展开更多
关键词 rotation energy transfer integral interference angle differential interference angle collision diameter
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Collisional Quantum Interference on Rotational Energy Transfer: Relation Between Integral Interference Angle and Rotational Quantum Number in Na2(A^1∑u^+,ν=8~b^3∏0u,ν=14)-Na System
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作者 WANG Wei-Li SONG Peng +2 位作者 LI Yong-Qing MIAO Gang MA Feng-Cai 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1X期123-129,共7页
Collisional quantum interference (CQI) on rotational energy transfer was observed in Na2(A^1∑u^+,ν=8~b^3∏0u,ν=14) system in collision with Na [Chem. Phys. Lett. 318 (2000) 107], and the degree of the inter... Collisional quantum interference (CQI) on rotational energy transfer was observed in Na2(A^1∑u^+,ν=8~b^3∏0u,ν=14) system in collision with Na [Chem. Phys. Lett. 318 (2000) 107], and the degree of the interference was measured. The integral interference angle was obtaJned through theoretical calculation. We will research the factors that have effect on collisional quantum interference on rotational energy transfer in Na2(A^1∑u^+,ν=8~b^3∏0u,ν=14)-Na system. Basing on the time-dependent first order Born approximation, and taking into account the anlsotroplc Lennard Jones interaction potentials and "straight-line" trajectory approximation, we obtain the factors that have effect on CQI in Na2-Na system, and obtain the relation between the integral interference angle and rotational quantum number. 展开更多
关键词 rotational energy transfer interference angle rotational quantum number
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Real-Time Dynamic Spectrum Analysis for Plasma Electron Density and Faraday Rotation Angle Measurement on HL-2A
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作者 丁宝钢 吴军 +3 位作者 范伟伟 吴彤宇 周艳 阴泽杰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第12期1092-1096,共5页
Electron density and Faraday rotation angle are important physical parameters in nuclear fusion research.To measure them simultaneously,the three-wave polarimeter/interferometer diagnostic system is applied.Both the f... Electron density and Faraday rotation angle are important physical parameters in nuclear fusion research.To measure them simultaneously,the three-wave polarimeter/interferometer diagnostic system is applied.Both the final probe output signal and the reference signal contain three frequency components.The time-varying phase difference curve of each frequency component can be measured by the Real-time Dynamic Spectrum Analysis(RDSA)method based on Field-Programmable Gate Array(FPGA).The phase difference precision is better than 0.1° and the real-time feedback delay is less than 1 ms,which satisfy the requirements of HL-2A. 展开更多
关键词 Electron Spectrum Faraday rotation interferometer satisfy performing angle instead rotating
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Novel Method for Spatial Angle Measurement Based on Rotating Planar Laser Beams 被引量:19
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作者 YANG Linghui YANG Xueyou ZHU Jigui DUAN Muqiong LAO Dabao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第6期758-764,共7页
Spatial angle measurement, especially the measurement of horizontal and vertical angle, is a basic method used for industrial large-scale coordinate measurement. As main equipments in use, both theodolites and laser t... Spatial angle measurement, especially the measurement of horizontal and vertical angle, is a basic method used for industrial large-scale coordinate measurement. As main equipments in use, both theodolites and laser trackers can provide very high accuracy for spatial angle measurement. However, their industrial applications are limited by low level of automation and poor parallelism. For the purpose of improving measurement efficiency, a lot of studies have been conducted and several alternative methods have been proposed. Unfortunately, all these means are either low precision or too expensive. In this paper, a novel method of spatial angle measurement based on two rotating planar laser beams is proposed and demonstrated. Photoelectric receivers placed on measured points are used to receive the rotating planner laser signals transmitted by laser transmitters. The scanning time intervals of laser planes were measured, and then measured point's horizontal/vertical angles can be calculated. Laser plane's angle parameters are utilized to establish the abstract geometric model of transmitter. Calculating formulas of receiver's horizontal/vertical angles have been derived. Measurement equations' solvability conditions and judgment method of imaginary solutions are also presented after analyzing. Proposed method for spatial angle measurement is experimentally verified through a platform consisting of one laser transmitter and one optical receiver. The transmitters used in new method are only responsible for providing rotating light plane signals carrying angle information. Receivers automatically measure scanning time of laser planes and upload data to the workstation to calculate horizontal angle and vertical angle. Simultaneous measurement of multiple receivers can be realized since there is no human intervention in measurement process .Spatial angle measurement result indicates that the repeatable accuracy of new method is better than 10". Proposed method can improve measurement's automation degree and speed while ensuring measurement accuracy. 展开更多
关键词 large-scale coordinate measurement spatial angle measurement rotating planar laser beams measurement automation
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Further Study of A-Related Quantum Interference of H-State Diatomic on Collision-Induced Rotational Energy Transfer 被引量:5
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作者 LI Yong-Qing SONG Peng +2 位作者 CHEN Yue-Hui WANG Wei-Li MA Feng-Cai 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2X期347-352,共6页
In our previous theoretical studies [Meng-Tao Sun, Yong-Qing Lee, and Feng-Cai Ma, Chem. Phys.Left. 371 (2003) 342], we have reported the quantum interference on collision-induced rotational energy transfer on CO (... In our previous theoretical studies [Meng-Tao Sun, Yong-Qing Lee, and Feng-Cai Ma, Chem. Phys.Left. 371 (2003) 342], we have reported the quantum interference on collision-induced rotational energy transfer on CO (A ^1 Π,v = 3) with inert gases, which originates from the difference between the two A-related collision potential energy surfaces. The interference angle, which measures the degree of coherence, is presented in this paper. Based on the time-dependent first order Born approximation, taking into account the anisotropic Lennard-Jones interaction potentials, the relation of the interference angle with the factors, including experimental temperature, partner, and rotational quantum number, are obtained. The changing tendencies with them are discussed. This theoretical model is important to understanding and performing this kind of experiment. 展开更多
关键词 quantum interference rotational energy transfer interference angle
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Rotation of the Earth as a Triaxial Rigid Body 被引量:6
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作者 SHEN Wenbin CHEN Wei +1 位作者 WANG Wenjun LIANG Yiqiang 《Geo-Spatial Information Science》 2007年第2期85-90,共6页
The Earth is taken as a triaxial rigid body, which rotates freely in the Euclidian space. The starting equations are the Euler dynamic equations, with A smaller than B and B smaller than C. The Euler equations are sol... The Earth is taken as a triaxial rigid body, which rotates freely in the Euclidian space. The starting equations are the Euler dynamic equations, with A smaller than B and B smaller than C. The Euler equations are solved, and the numerical results are provided. In the calculations, the following parameters are used: (C-B)/A=0.003 273 53; (B-A)/C=0.000 021 96; (C-A)/B=0.003 295 49, and the mean angular velocity of the Earth's rotation, ω =0.000 072 921 15 rad/s. Calculations show that, besides the self-rotation of the Earth and the free Euler procession of its rotation, there exists the free nutation: the nutation angle, or the angle between the Earth's momentary rotation axis and the mean axis that periodically change with time. The free nutation is investigated. 展开更多
关键词 Earth's rotation triaxial rigid body problem variation of Eulerian angles
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Frequency domain polarization weighted ESPRIT method for bearing angle 被引量:2
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作者 Wei Liu Shengchun Piao +2 位作者 Junyuan Guo Qingxin Meng Hanhao Zhu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第5期769-775,共7页
The signal to noise ratio (SNR) of seismic waves is usually very low after long distance transmission. For this condition, to improve the bearing estimation capability in the low SNR, a frequency domain polarization... The signal to noise ratio (SNR) of seismic waves is usually very low after long distance transmission. For this condition, to improve the bearing estimation capability in the low SNR, a frequency domain polarization weighted ESPRIT method using a single vector device is proposed. The frequency domain polari- zation parameters extracted from the signals are used to design the weighted function which is applied to the received signals. The bearing angle and the target frequency are estimated through ESPRIT using the weighted signals. The simulation and experiment results show that the presented method can obtain accurate estimation values under the low SNR with little prior information. 展开更多
关键词 vector seismic signal frequency domain polarizationweight bearing angle estimation estimation of signal parametersvia rotational invariance techniques (ESPRIT).
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∧-related Quantum Interference of ^2П [Case(a)] Diatom on Rotational Energy Transfer 被引量:2
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作者 Jian Li Yan-qing Ni +2 位作者 Yong-qing Li Wei-li Wang Feng-cai Ma 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第1期13-18,共6页
To study theoretically the relationship between the integral interference angle and the scat- tering angle in collisional quantum interference, the integral interference angle of atom- ^2П[case(a)] diatomic molecul... To study theoretically the relationship between the integral interference angle and the scat- tering angle in collisional quantum interference, the integral interference angle of atom- ^2П[case(a)] diatomic molecules system is described. To simulate the experiment theoretically, the theoretical model on collision-induced rotational energy transfer in an atom- ^2П[case(a)]diatom system is presented based on the first order Born approximation taking into account of the long-range interaction potential. For the ^2П electronic state in the Hund's case(a) diatom, the degree of the interference is discussed. The interference angles of collision-induced rotational energy transfer of CN(A^2П) in Hund's case(a) with He, Ne, and Ar are calculated quantitatively. The key parameters in the determination of integral interference angles are obtained. 展开更多
关键词 Collisional quantum interference rotational energy transfer Interference angle
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Usefulness of computed tomography based three-dimensional reconstructions to assess the critical shoulder angle 被引量:2
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作者 Dominic Mah Uphar Chamoli Geoffrey CS Smith 《World Journal of Orthopedics》 2021年第5期301-309,共9页
BACKGROUND The critical shoulder angle(CSA)is a radiographic measurement that provides an assessment of both glenoid inclination and acromial length.Higher values may correlate with the presence of rotator cuff tears.... BACKGROUND The critical shoulder angle(CSA)is a radiographic measurement that provides an assessment of both glenoid inclination and acromial length.Higher values may correlate with the presence of rotator cuff tears.However,it is difficult to obtain a high-quality true anteroposterior(AP)radiograph of the shoulder,with any excess scapular version or flexion/extension resulting in deviation from the true CSA value.Three-dimensional(3D)bony reconstructions of computed tomography(CT)shoulder scans may be able to be rotated to obtain a similar view to that of true AP radiographs.AIM To compare CSA measurements performed on 3D bony CT reconstructions,with those on corresponding true AP radiographs.METHODS CT shoulder scans were matched with true AP radiographs that were classified as either Suter-Henninger type A or C quality.3D bony reconstructions were segmented from the CT scans,and rotated to replicate an ideal true AP view.Two observers performed CSA measurements using both CT and radiographic images.Measurements were repeated after a one week interval.Reliability was assessed using intraclass correlation coefficients(ICCs)and Bland-Altman plots[bias,limits of agreement(LOA)].RESULTS Twenty CT shoulder scans were matched.The mean CSA values were 32.55°(±4.26°)with radiographs and 29.82°(±3.49°)with the CT-based method[mean difference 2.73°(±2.86°);P<0.001;bias+2.73°;LOA-2.17°to+7.63°].There was a strong correlation between the two methods(r=0.748;P<0.001).Intra-observer reliability was similar,but the best intra-observer values were achieved by the most experienced observer using the CT-based method[ICC:0.983(0.958-0.993);bias+0.03°,LOA-1.28°to+1.34°].Inter-observer reliability was better with the CT-based method[ICC:0.897(0.758-0.958),bias+0.24°,LOA-2.93°to+3.41°].CONCLUSION The described CT-based method may be a suitable alternative for critical shoulder angle measurement,as it overcomes the difficulty in obtaining a true AP radiographic view. 展开更多
关键词 Critical shoulder angle Computed tomography Osteoarthritis rotator cuff tear Acromioplasty Arthroscopic lateral acromial resection
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Relationship Between Differential Interference Angle and Parameter of Experiment in Molecular Beam 被引量:1
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作者 LI Yong-Qing LI Jian MA Feng-Cai 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2X期294-296,共3页
Collisional quantum interference (CQI) was observed in the intramolecular rotational energy transfer in the experiment of the static cell, and the integral interference angles were measured. To observe more precise ... Collisional quantum interference (CQI) was observed in the intramolecular rotational energy transfer in the experiment of the static cell, and the integral interference angles were measured. To observe more precise information, the experiment in the molecular beam should be taken,from which the relationship between the differential interference angle and the scattering angle can be obtained. In this paper, the theoretical model of CQI is described in an atom-diatom system in the condition of the molecular beam, based on the first-Born approximation of time-dependent perturbation theory, taking into accounts the long-range interaction potential. The method of observing and measuring correctly the differential interference angle is presented. The changing tendency of the differential interference angle with the impact parameter and relative velocity is discussed. The changing tendencies of the differential interference angle with the parameter of experiment in the molecular beam, including the impact parameter and the velocity are discussed. This theoretical model is important to understand or perform the experiment in the molecular beam. 展开更多
关键词 differential interference angle quantum interference rotational energy transfer
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Open-closed Loop ILC Corrected with Angle Relationship of Output Vectors for Tracking Control of Manipulator 被引量:8
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作者 WANG Hong-Bin WANG Yan 《自动化学报》 EI CSCD 北大核心 2010年第12期1758-1765,共8页
关键词 ILC 自动化 跟踪控制 仿真
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Experimental Study on Rotation Resistance Coefficient of Motor Bogie for Type A Vehicle
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作者 Fuxing Tan Hongtao Liu +2 位作者 Shihui Liu Zhenchuan Zhang Peng Zhang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2019年第2期90-96,共7页
Rotation resistance coefficient is an important operating parameter for vehicle bogies, which influences the dynamic behavior of vehicles directly. A research on the rotation resistance coefficient of type A vehicle m... Rotation resistance coefficient is an important operating parameter for vehicle bogies, which influences the dynamic behavior of vehicles directly. A research on the rotation resistance coefficient of type A vehicle motor bogies was conducted by means of theoretical calculation, dynamic simulation, test certification, and so on. Result of the simulation analysis shows that the rotation resistance coefficient relates to air springs stiffness and negotiated curve radii, and it varies proportionally with the change of air springs horizontal stiffness. The greater the rotation angle is, the greater the factor becomes. The certifications made under the operating conditions(e.g., different air spring status, different rotation speeds) indicate that the rotation resistance coefficient increases with the increase of the rotation speed. The anti-yaw dampers can contribute to the rotation resistance torque acted on bogie, and the greater the rotation speeds are, the greater the torque generated by the anti-yaw dampers is. The results suggest that the theoretical analysis and dynamics simulation are in accordance with the results from the bogie bench tests, which meet the requirements in EN14363 and the indicators in vehicles safe operation. 展开更多
关键词 type A VEHICLE MOTOR BOGIE rotation angle rotation resistance COEFFICIENT rotation SPEED
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Research and Simulation of Navigation Control System for Agricultural Unmanned Rotation Rotorcraft
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作者 Ma Chen-ming Su Zhong-bin Zhang Zong-xin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2019年第3期87-96,共10页
In order to improve the efficiency of field operations, such as pesticide spraying and pest control, the development of new agricultural machinery has become the main goal of agricultural modernization. At present, sm... In order to improve the efficiency of field operations, such as pesticide spraying and pest control, the development of new agricultural machinery has become the main goal of agricultural modernization. At present, small unmanned aerial vehicles(UAVs) have achieved good results in small area pesticide spraying, but they still do not meet the requirements of the big field operations. The rotation rotorcraft has the characteristics of low speed, good safety, super stol, strong endurance, strong wind resistance and simple mechanism, so it is very suitable for farmland operation. But at present, there are relatively few researches on the unmanned rotation rotorcraft at domestic and abroad, and there is no mature control theory system of unmanned rotation rotorcraft. Therefore, in order to solve the problem of navigation control system of unmanned rotation rotorcraft, the navigation control strategy of the rotation rotorcraft was studied in this paper, and the flight control strategy of the rotation rotorcraft was divided into two parts, the linear control and the turn control. The lateral correction strategy was used to control the rotorcraft, so as to complete the track guidance of the rotation rotorcraft. Using the matrix laboratory(MATLAB) modeling to simulate the circular trajectory and the serpentine trajectory, the maximum deviation of circular path offset was 1.1 m. The variance between the path angle and the given path angle was 6°. The maximum deviation of serpentine path offset was 0.6 m. The variance between the path angle and the given path angle was 8°. The simulation results showed that the rotorcraft could accomplish the scheduled trajectory task based on this control strategy. 展开更多
关键词 rotation ROTORCRAFT TURN CONTROL deviation angle CONTROL
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