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Research on Transmission Line Tower Tilting and Foundation State Monitoring Technology Based onMulti-Sensor Cooperative Detection and Correction
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作者 Guangxin Zhang Minghui Liu +4 位作者 Shichao Cheng Minzhen Wang Changshun Zhao Hongdan Zhao Gaiming Zhong 《Energy Engineering》 EI 2024年第1期169-185,共17页
The transmission line tower will be affected by bad weather and artificial subsidence caused by the foundation and other factors in the power transmission.The tower’s tilt and severe deformation will cause the buildi... The transmission line tower will be affected by bad weather and artificial subsidence caused by the foundation and other factors in the power transmission.The tower’s tilt and severe deformation will cause the building to collapse.Many small changes caused the tower’s collapse,but the early staff often could not intuitively notice the changes in the tower’s state.In the current tower online monitoring system,terminal equipment often needs to replace batteries frequently due to premature exhaustion of power.According to the need for real-time measurement of power line tower,this research designed a real-time monitoring device monitoring the transmission tower attitude tilting and foundation state based on the inertial sensor,the acceleration of 3 axis inertial sensor and angular velocity raw data to pole average filtering pre-processing,and then through the complementary filtering algorithm for comprehensive calculation of tilt angle,the system meets the demand for inclined online monitoring of power line poles and towers regarding measurement accuracy,with low cost and power consumption.The optimization multi-sensor cooperative detection and correction measured tilt angle result relative accuracy can reach 1.03%,which has specific promotion and application value since the system has the advantages of unattended and efficient calculation. 展开更多
关键词 Transmission line tower tilting MULTI-SENSOR foundation state monitoring collaborative detection
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基于伪磁梯度张量混合方向tilt梯度的磁源定位方法及其应用:以内蒙古塔木素铀矿床为例
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作者 王彦国 林昭翰 +3 位作者 邓居智 郭华 郝梦成 Sulaiman Garba Yana 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2024年第5期2043-2056,共14页
斜磁化磁源的准确定位是磁法勘探有效圈定场源分布及划分断裂构造的重要依据.但受磁化方向影响,总磁异常与地质体分布并无明显对应关系.为此,本文从总磁异常垂向积分出发,推导出了伪磁梯度张量,定义了伪磁梯度张量的混合方向tilt梯度及... 斜磁化磁源的准确定位是磁法勘探有效圈定场源分布及划分断裂构造的重要依据.但受磁化方向影响,总磁异常与地质体分布并无明显对应关系.为此,本文从总磁异常垂向积分出发,推导出了伪磁梯度张量,定义了伪磁梯度张量的混合方向tilt梯度及混合方向解析信号振幅,提出了基于伪磁梯度张量混合方向tilt梯度水平导数组合的场源定位方法.模型试验表明,相对于解析信号振幅、tilt梯度的总水平导数及方向tilt梯度的总水平导数模这3种受磁化方向影响较小的方法,本文提出的磁源定位方法能够更有效地反映出不同磁化方向的磁源位置,具有更强的识别能力和定位精度.在内蒙古塔木素铀矿床的航磁资料应用中,新方法较好地展示出了已知断裂带的展布及出露岩浆岩的分布,同时有效地提取了塔木素铀矿床上方的弱磁异常信息,处理结果为研究区圈定隐伏岩体、划分隐伏断裂及扩大铀矿找矿靶区提供了依据. 展开更多
关键词 总磁异常 磁梯度张量 方向tilt梯度 磁源定位 塔木素铀矿床
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基于多CNN的分块镜piston和tip-tilt误差同步检测方法研究
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作者 李响 赵伟瑞 《仪器仪表学报》 EI CAS CSCD 北大核心 2024年第3期188-197,共10页
绝大多数大型望远镜采用分块镜的设计方案,为了获得优质的成像效果,需要控制分块望远镜系统的piston和tip-tilt误差。神经网络误差检测方法相较于传统的检测方法具有一定优势,但存在仅检测单一类型误差的局限性。本文提出一种基于卷积... 绝大多数大型望远镜采用分块镜的设计方案,为了获得优质的成像效果,需要控制分块望远镜系统的piston和tip-tilt误差。神经网络误差检测方法相较于传统的检测方法具有一定优势,但存在仅检测单一类型误差的局限性。本文提出一种基于卷积神经网络的piston和tip-tilt误差同步检测方法,通过在出瞳面设置具有离散孔的光阑,引发分段镜反射的子波发生干涉-衍射现象,构建包含丰富piston和tip-tilt误差信息的数据集。通过粗测网络和精测网络级联,满足大范围和高精度同步检测的需求。结果表明,该方法实现了对输入光源相干长度内纳米级的piston误差检测,并对10μrad范围内的tip-tilt误差实现了亚微弧度检测;对40 dB的CCD噪声表现出良好的抗干扰性,对面形误差的允差为0.05λ0RMS(λ0=600 nm),同时对六子镜系统具有可扩展性。本文方法光路简单,操作便利,具有实际意义。 展开更多
关键词 piston误差 tip-tilt误差 分块镜 卷积神经网络
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Tilt-up建筑波纹钢板屋盖平面内抗震设计方法研究
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作者 韩健翮 彭有开 吴徽 《工程建设与设计》 2024年第3期15-19,共5页
Tilt-up建筑体系是一种由钢筋混凝土墙板、屋盖、内部承重柱组成的“盒式”受力体系。屋盖作为重要的结构构件,不仅承受平面外荷载,还承受由地震作用产生的水平力。论文分析了屋盖平面内受力机理,介绍了美国ASCE 7规范、IBC规范中Tilt-u... Tilt-up建筑体系是一种由钢筋混凝土墙板、屋盖、内部承重柱组成的“盒式”受力体系。屋盖作为重要的结构构件,不仅承受平面外荷载,还承受由地震作用产生的水平力。论文分析了屋盖平面内受力机理,介绍了美国ASCE 7规范、IBC规范中Tilt-up结构波纹钢板屋盖平面内抗震设计方法,对华盛顿地区某Tilt-up建筑波纹钢板屋盖进行了设计研究,为我国引入Tilt-up建筑体系提供参考。 展开更多
关键词 tilt-up建筑 波纹钢板屋盖 平面内受力 设计方法
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Analytical solution for the effective elastic properties of rocks with the tilted penny-shaped cracks in the transversely isotropic background
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作者 Zheng-Qian Ma Xing-Yao Yin +2 位作者 Zhao-Yun Zong Yuan-Yuan Tan Ya-Ming Yang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期221-243,共23页
Seismic prediction of cracks is of great significance in many disciplines,for which the rock physics model is indispensable.However,up to now,multitudinous analytical models focus primarily on the cracked rock with th... Seismic prediction of cracks is of great significance in many disciplines,for which the rock physics model is indispensable.However,up to now,multitudinous analytical models focus primarily on the cracked rock with the isotropic background,while the explicit model for the cracked rock with the anisotropic background is rarely investigated in spite of such case being often encountered in the earth.Hence,we first studied dependences of the crack opening displacement tensors on the crack dip angle in the coordinate systems formed by symmetry planes of the crack and the background anisotropy,respectively,by forty groups of numerical experiments.Based on the conclusion from the experiments,the analytical solution was derived for the effective elastic properties of the rock with the inclined penny-shaped cracks in the transversely isotropic background.Further,we comprehensively analyzed,according to the developed model,effects of the crack dip angle,background anisotropy,filling fluid and crack density on the effective elastic properties of the cracked rock.The analysis results indicate that the dip angle and background anisotropy can significantly either enhance or weaken the anisotropy degrees of the P-and SH-wave velocities,whereas they have relatively small effects on the SV-wave velocity anisotropy.Moreover,the filling fluid can increase the stiffness coefficients related to the compressional modulus by reducing crack compliance parameters,while its effects on shear coefficients depend on the crack dip angle.The increasing crack density reduces velocities of the dry rock,and decreasing rates of the velocities are affected by the crack dip angle.By comparing with exact numerical results and experimental data,it was demonstrated that the proposed model can achieve high-precision estimations of stiffness coefficients.Moreover,the assumption of the weakly anisotropic background results in the consistency between the proposed model and Hudson's published theory for the orthorhombic rock. 展开更多
关键词 Effective elastic property tilted crack Transverse isotropy Analytical solution Crack opening displacement
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Analysis and Research on Aerodynamic Characteristics of Quad Tilt Rotor Aircraft
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作者 Jike Jia Xiaomei Ye +2 位作者 Guoyi He Qingjin Huang Zhile Hong 《Advances in Aerospace Science and Technology》 2024年第1期28-39,共12页
For the quad tilt rotor aircraft, a computational fluid dynamics method based on multiple reference frames (MRF) was used to analyze the influence of aerodynamic layout parameters on the aerodynamic characteristics of... For the quad tilt rotor aircraft, a computational fluid dynamics method based on multiple reference frames (MRF) was used to analyze the influence of aerodynamic layout parameters on the aerodynamic characteristics of the quad tilt rotor aircraft. Firstly, a numerical simulation method for the interference flow field of the quad tilt rotor aircraft is established. Based on this method, the aerodynamic characteristics of isolated rotors, rotor combinations at different lateral positions on the wing, and rotor rotation directions under different inflow velocities were calculated and analyzed, in order to grasp their aerodynamic interference laws and provide reference for the design and control theory research of such aircraft. 展开更多
关键词 Quad tilt Rotor Aircraft Analysis of Aerodynamic Characteristics CFD Method
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Tilt Angle Optimality Criteria for Stand Alone PV Systems
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作者 Mohammad Abu-Naser 《Journal of Power and Energy Engineering》 2024年第3期1-18,共18页
The conventional approach to optimizing tilt angles for fixed solar panels aims to maximize energy generation over the entire year. However, in the context of a supply controlled electric grid, where solar energy avai... The conventional approach to optimizing tilt angles for fixed solar panels aims to maximize energy generation over the entire year. However, in the context of a supply controlled electric grid, where solar energy availability varies, this criterion may not be optimal. This study explores two alternative optimization criteria focused on maximizing baseload supply potential and minimizing required storage capacity to address seasonality in energy generation. The optimal tilt angles determined for these criteria differed significantly from the standard approach. This research highlights additional factors crucial for designing solar power systems beyond gross energy generation, essential for the global transition towards a fully renewable energy-based electric grid in the future. 展开更多
关键词 Electric Grid Fixed Solar Panels Optimal PV tilt Angle Seasonal Solar Variability Renewable Energy Supply-Demand Balance
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π-凝聚环上的广义Morita对偶及Tilting定理 被引量:1
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作者 刘敏 李尚莹 《内江师范学院学报》 2002年第4期6-13,共8页
本文建立了 π-凝聚环上有限生成无挠模范畴的 Tilting定理及相关的广义Morita对偶。推广了 Colby有关
关键词 tilting定理 Π-凝聚环 有限生成无挠模 广义Morita对偶 tilting tilting
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量子群主Tilting模的张量积及其滤过 被引量:1
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作者 柏元淮 《数学年刊(A辑)》 CSCD 北大核心 2001年第2期229-236,共8页
A= Z[v]Ω,Ω Z[v]的由-1和奇p生成的理想. U是 A上的量子代数.令 фp是 p次分圆多项式, B= A/(фp),г 是商代数 B关于理想(ζ— 1)的完备化,式中ζ是p次本原根.对人 λ∈ X+, Mг(λ)表首... A= Z[v]Ω,Ω Z[v]的由-1和奇p生成的理想. U是 A上的量子代数.令 фp是 p次分圆多项式, B= A/(фp),г 是商代数 B关于理想(ζ— 1)的完备化,式中ζ是p次本原根.对人 λ∈ X+, Mг(λ)表首权为λ的不可分解 Uг-Tiltins模(称为主 Uг模).本文给出了量子群主 Uг模的张量积定理.对 p≥ 2(h-1),在 p2室中描述了量子群主 Uг模好滤过滤过商之首权的分布状态及其滤过重数作为例子,对秩1型和 A2型的量子群情形给出了 P2室中一般位置室主 Uг模好滤过的分解模式. 展开更多
关键词 量子群 不可分解模 tilting 滤过 张量积定理 理想 分解模式
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Wakamatsu tilting模的性质
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作者 邢建民 李秀丽 《科学技术与工程》 2009年第2期360-361,共2页
设Λ为Artin代数,对给定的Wakamatsu tilting模,Wakamatsu tilting cotorsionpair以及相关类的性质。
关键词 Wakamatsu tilting 模核 预覆盖 自正交 cotorsion PAIR
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Dual pairs of tilting pairs
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作者 廖贻华 陈建龙 《Journal of Southeast University(English Edition)》 EI CAS 2011年第3期347-350,共4页
A module pair (C, T) over an Artin algebra A is called a tilting pair if both C and T are selforthogonal modules and the conditions T e ada C and C ∈ add T hold. The duality on a tilting pair is investigated to dis... A module pair (C, T) over an Artin algebra A is called a tilting pair if both C and T are selforthogonal modules and the conditions T e ada C and C ∈ add T hold. The duality on a tilting pair is investigated to discuss the condition under which the dual of a tilting pair is also a tilting pair. A necessary and sufficient condition of (D(7), D(C) ) being an n-tilting pair over an Artin algebra for an n-tilting pair ( C, 7) is given. And, a necessary and sufficient condition of ( T^*, C^* ) being an ntilting pair over a selfinjective Artin algebra for an n-tilting pair (C, 7) is also given. 展开更多
关键词 selforthogonal module selfinjective dual module tilting pair
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量子群主Tilting模的形式特征标
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作者 柏元淮 《暨南大学学报(自然科学与医学版)》 CAS CSCD 2001年第5期1-9,共9页
设p≥ 2 (h- 1) ,λ∈X+ 是p2 室中的正则支配权 .证明了主UΨ 模MΨ(λ0 +Pλ1)的形式特征标公式 ;描述了MΨ(λ0 +pλ1)的合成因子的分布状态 .对于A2 型量子群 ,给出了p2 室一般位置室中UΨ 模范畴主UΨ 模MΨ(λ0 +Pλ1)合成因子的... 设p≥ 2 (h- 1) ,λ∈X+ 是p2 室中的正则支配权 .证明了主UΨ 模MΨ(λ0 +Pλ1)的形式特征标公式 ;描述了MΨ(λ0 +pλ1)的合成因子的分布状态 .对于A2 型量子群 ,给出了p2 室一般位置室中UΨ 模范畴主UΨ 模MΨ(λ0 +Pλ1)合成因子的分解模式 . 展开更多
关键词 量子群 不可分解模 tilting 形式特征标 正则支配权 分解模式
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π-凝聚环上的余*-模和余tilting模
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作者 刘敏 汪明义 左平 《四川师范大学学报(自然科学版)》 CAS CSCD 2003年第1期33-37,共5页
主要引入了π 凝聚环上的余 模和余tilting模的概念.得到了余 模的3个刻划,并且利用余 模给出了π 凝聚环上余tilting模的特征性质,从而推广了文献(ScienceinChina,1995,39(1):1709~1728.)中的结果.
关键词 Π-凝聚环 余*-模 tilting 生成子 有限生成无挠 酋模
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Tilting Ratchet肌动蛋白双足运动模型的研究
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作者 王丹 邓迎春 《湖南城市学院学报(自然科学版)》 CAS 2006年第4期32-35,共4页
针对肌动蛋白两足交替行走的事实提出了Tilting ratchet双足运动模型,并对其运动轨道进行了数学模拟.从而说明所提出的模型能够清楚的描述这种交替行走的运动机制,表明了模型的可行性和有效性.同时还对这种模型中的粒子运动速度和系统... 针对肌动蛋白两足交替行走的事实提出了Tilting ratchet双足运动模型,并对其运动轨道进行了数学模拟.从而说明所提出的模型能够清楚的描述这种交替行走的运动机制,表明了模型的可行性和有效性.同时还对这种模型中的粒子运动速度和系统效率进行了研究,给出了一些数值模拟结果. 展开更多
关键词 分子马达 肌动蛋白 tilting ratchet模型 耦合扩散过程 马达效率
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Study on general inverse kinematics of rotating/tilting positioner for robotic arc welding off-line programming 被引量:3
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作者 田劲松 吴林 戴明 《China Welding》 EI CAS 2001年第1期27-33,共7页
Off line programming provides an essential link between CAD and CAM, whose development will result in greater use of robotic arc welding. An arc welding system with a robot and a rotating/tilting positioner is one of... Off line programming provides an essential link between CAD and CAM, whose development will result in greater use of robotic arc welding. An arc welding system with a robot and a rotating/tilting positioner is one of the most typical workcells. The inverse kinematics of robot and positioner is the foundation of the off line programming system. The previous researchers only focused on a special solution of the positioner inverse kinematics, which is the solution at down hand welding position. In this paper, we introduce a method for representing welding position. Then a general algorithm of rotating/tilting positioner inverse kinematics is presented, and an approach to find the unique solution of the inverse kinematics is discussed. The simulation experiment results show that the general algorithm can improve the ability of robotic arc welding off line programming system to program all types of welding positions. 展开更多
关键词 robotic arc welding off line programming rotating/tilting positioner inverse kinematics
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A Study on the Characteristics for the Ground Vibration Due to the Travelling Tilting Train 被引量:2
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作者 Hee Seok Kim 《Engineering(科研)》 2013年第9期729-734,共6页
The development of the tilting train can contribute to solve the economic burden and enhance the transportation means of areas that did not share the benefits of the high speed railway. But the dynamic behavior caused... The development of the tilting train can contribute to solve the economic burden and enhance the transportation means of areas that did not share the benefits of the high speed railway. But the dynamic behavior caused by the interaction between the train and the track as well as the environmental vibrations along the railway should be evaluated to secure the safety of the train and riding comfort. In this paper a study on the characteristics for ground vibration due to the tilting train travelling in the conventional line are carried out. The transmitted load into the ground is computed through a study on the interrelation between the tilting car and the line. This load is applied into the numerical model which is one for the analysis of ground vibration due to the travelling tilting car. The far fields on the numerical model are formed by the absorbing boundary using dashpot, one of the most widely used absorbing boundary in finite element analysis. Using this numerical model, the analysis of the ground vibration characteristics caused by travelling tilting car is performed. From the analysis, it is shown that the transferred load due to the tilting train is larger than that of the conventional train. 展开更多
关键词 GROUND VIBRATION tilting CAR Absorbing BOUNDARY
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Stability Analysis on Rotor Systems Supported by Self-acting Tilting-pad Gas Bearings with Frequency Effects 被引量:4
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作者 YANG Lihua QI Shemiao +1 位作者 GENG Haipeng YU Lie 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第3期380-385,共6页
The recent research on stability of gas bearing-rotor systems still mostly adopts the same method as in oil-lubricated bearing-rotor systems.The dynamic coefficients of gas bearings in the case that the perturbation f... The recent research on stability of gas bearing-rotor systems still mostly adopts the same method as in oil-lubricated bearing-rotor systems.The dynamic coefficients of gas bearings in the case that the perturbation frequencies are same as the rotating speed are used to carry out the stability analysis of rotor systems.This method does not contact the frequency characteristics of dynamic stiffness and damping coefficients of gas bearings with the dynamical behaviors of rotor systems.Furthermore,the effects of perturbation frequencies on the stability of systems are not taken into account.In this paper,the dynamic stiffness and damping coefficients of tilting-pad gas bearings are calculated by the partial derivative method.On the base of solution of dynamic coefficients,two computational models are produced for stability analysis on rotor systems supported by tilting-pad gas bearings according to whether the degrees of the freedom of pads tilting motions are included in the equations of motion or not.In the condition of considering the frequency effects of dynamic coefficients of tilting-pad gas bearings,the corresponding eigenvalues of the rigid and first five vibration modes of the system with the working speeds of 8-30 kr/min are computed through iteratively solving the equations of motion of rotor-system by using two computational models,respectively.According to the obtained eigenvalues,the stability of rotor system is analyzed.The results indicate that the eigenvalues and the stability of rotor system obtained by these two computational models are well agreement each other.They all can more accurately analyze the stability of rotor systems supported by tilting-pad gas bearings.This research has important meaning for perfecting the stability analysis method of rotor systems supported by gas bearings. 展开更多
关键词 bearing-rotor system tilting-pad bearing logarithm attenuation rate stability analysis
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STUDY ON DYNAMIC CURVING BEHAVIOR OF TILTING PASSENGER CARS
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作者 Liu Hongyou Zeng Jing National Traction Power Laboratory, Southwest Jiaotong University, Chengdu 610031, China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2002年第4期360-365,371,共7页
By using tilting carbodies, train can negotiate at a higher speed withoutreducing the passenger's ride quality. This is a good method to allow a significant increase inspeed at existing track to improve the railwa... By using tilting carbodies, train can negotiate at a higher speed withoutreducing the passenger's ride quality. This is a good method to allow a significant increase inspeed at existing track to improve the railway transportation capability, and to enhance thecompetition ability of railways with other transportation systems. With the increase of the curvenegotiation speed, the wheel-rail lateral forces and wheel-rail wear of the tilting train willincrease. The self-steering radial bogie is an effective way to solve the problem. The dynamic modelof the tilting passenger car with self-steering bogies is established in detail, and the curvingperformance of the car is investigated. 展开更多
关键词 tilting passenger car self-steering bogie dynamic curving behavior wheel-rail interaction
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Realization of Tip Tilting By 8-Step Line Tilting
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作者 CHEN Ying-Tian ZHANG Yang +3 位作者 HU Sen HO Tso-Hsiu Boon Ham Lim Chen Sin Lim 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第9期549-554,共6页
By direct calculation of rotation matrices of SO(3),we show how certain specific sequence of eight consecutiverotations of digital angles can yield a tilting of a facet mirror.We also design a detailed program specifi... By direct calculation of rotation matrices of SO(3),we show how certain specific sequence of eight consecutiverotations of digital angles can yield a tilting of a facet mirror.We also design a detailed program specifically to tiltan array of mirrors from planar orientation to the required focusing orientation.We describe how to use the 8-step torealize the focusing of the mirror array.We have found,in our designed program,an important feature of row-sharingduring the rotations for the columns and similarly the column-sharing during the rotations for the row.This feature cansave a lot of operating time during the actual realization of the mechanical movements. 展开更多
关键词 rotational group solar energy optical device tip tilting line tilting
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Realization of Fine Tip Tilting by 16-Step Line Tilting
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作者 丁璐 陈应天 +1 位作者 胡森 张杨 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第7期175-180,共6页
Following Chen's method [Commun. Theor. Phys. 52 (2009) 549] to use &step line tilting to realize tip tilting, to achieve finer rotation, it is discovered that a 16-step line tilting method may realize a rotation ... Following Chen's method [Commun. Theor. Phys. 52 (2009) 549] to use &step line tilting to realize tip tilting, to achieve finer rotation, it is discovered that a 16-step line tilting method may realize a rotation two order smaller than that achieved by &step. 展开更多
关键词 rotation group tip tilting line tilting
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