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Error analysis and optimization of a 3-degree of freedom translational Parallel Kinematic Machine

null

《机械工程前沿（英文）》 2014年 第9卷 第2期   页码 120-129 doi: 10.1007/s11465-014-0300-3

摘要：

In this paper, error modeling and analysis of a typical 3-degree of freedom translational Parallel Kinematic Machine is presented. This mechanism provides translational motion along the Cartesian X-, Y- and Z- axes. It consists of three limbs each having an arm and forearm with prismatic-revolute-revolute-revolute joints. The moving or tool platform maintains same orientation in the entire workspace due to its joint arrangement. From inverse kinematics, the joint angles for a given position of tool platform necessary for the error modeling and analysis are obtained. Error modeling is done based on the differentiation of the inverse kinematic equations. Variation of pose errors along X, Y and Z directions for a set of dimensions of the parallel kinematic machine is presented. A non-dimensional performance index, namely, global error transformation index is used to study the influence of dimensions and its corresponding global maximum pose error is reported. An attempt is made to find the optimal dimensions of the Parallel Kinematic Machine using Genetic Algorithms in MATLAB. The methodology presented and the results obtained are useful for predicting the performance capability of the Parallel Kinematic Machine under study.

关键词： translational Parallel Kinematic Machine     error modeling     global error transformation index    

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SUSTAINABLE NITROGEN MANAGEMENT INDEX: DEFINITION, GLOBAL ASSESSMENT AND POTENTIAL IMPROVEMENTS

《农业科学与工程前沿（英文）》 2022年 第9卷 第3期   页码 356-365 doi: 10.15302/J-FASE-2022458

摘要：

● A composite N management index is proposed to measure agriculture sustainability.

关键词： global assessment     indicator     nitrogen management     sustainable agriculture     sustainable development goals    

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Theoretical prediction and validation of global horizontal solar irradiance for a tropical climate in

Sivasankari SUNDARAM,Jakka SARAT CHANDRA BABU

《能源前沿（英文）》 2015年 第9卷 第3期   页码 311-321 doi: 10.1007/s11708-015-0369-3

摘要： This paper aims to propose monthly models responsible for the theoretical evaluation of the global horizontal irradiance of a tropical region in India which is Sivagangai situated in Tamilnadu. The actual measured global horizontal irradiance hails from a 5 MW solar power plant station located at Sivagangai in Tamilnadu. The data were monitored from May 2011 to April 2013. The theoretical assessment was conducted differently by employing a programming platform called Microsoft Visual Basic 2010 Express. A graphical user interface was created using Visual Basic 2010 Express, which provided the evaluation of empirical parameters for model formulation such as daily sunshine duration ( ), maximum possible sunshine hour duration ( ), extra terrestrial horizontal global irradiance ( ) and extra terrestrial direct normal irradiance ( ). The proposed regression models were validated by the significance of statistical indicators such as mean bias error, root mean square error and mean percentage error from the predicted and the actual values for the region considered. Comparison was made between the proposed monthly models and the existing normalized models for global horizontal irradiance evaluation.

关键词： global horizontal irradiance (GHI)     mean bias error     root mean square error     mean percentage error     coefficient of regression     Visual Basic 2010 Express    

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Toward energy finance market transition: Does China’s oil futures shake up global spots market?

《工程管理前沿（英文）》   页码 409-424 doi: 10.1007/s42524-022-0207-3

摘要： China is breaking through the petrodollar system, establishing RMB-dominating crude oil futures market. The country is achieving a milestone in its transition to energy finance market internationalization. This study explores the price leadership of China’s crude oil futures and identifies its price co-movement to uncover whether it truly shakes up the global oil spots market. First, we find that for oil spots under different gravities, China’s oil futures is only a net price information receiver from light-, medium-, and heavy-gravity oil spots, but it has a relatively stronger price co-movement with these three spots. Second, for oil spots under different sulfur contents, China’s oil futures still has weak price leadership in sweet, neutral, and sour oil spots, but it has strong co-movement with them. Third, for oil spots under different geographical origins, China’s oil futures shows price leadership in East Asian and Australian oil spots at the medium- and long-run time scales and strong price co-movement with East Asian, Middle Eastern, Latin American and Australian oil spots. China’s oil futures may not have good price leadership in global spots market, but it features favorable price co-movement.

关键词： China’s oil futures     price information spillover     price co-movement     BK spillover index     BDECO model    

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Chord error constraint based integrated control strategy for contour error compensation

Tie ZHANG, Caicheng WU, Yanbiao ZOU

《机械工程前沿（英文）》 2020年 第15卷 第4期   页码 645-658 doi: 10.1007/s11465-020-0601-7

摘要： As the traditional cross-coupling control method cannot meet the requirements for tracking accuracy and contour control accuracy in large curvature positions, an integrated control strategy of cross-coupling contour error compensation based on chord error constraint, which consists of a cross-coupling controller and an improved position error compensator, is proposed. To reduce the contour error, a PI-type cross-coupling controller is designed, with its stability being analyzed by using the contour error transfer function. Moreover, a feed rate regulator based on the chord error constraint is proposed, which performs speed planning with the maximum feed rate allowed by the large curvature position as the constraint condition, so as to meet the requirements of large curvature positions for the chord error. Besides, an improved position error compensation method is further presented by combining the feed rate regulator with the position error compensator, which improves the tracking accuracy via the advance compensation of tracking error. The biaxial experimental results of non-uniform rational B-splines curves indicate that the proposed integrated control strategy can significantly improve the tracking and contour control accuracy in biaxial contour following tasks.

关键词： cross-coupling controller     contour error     tracking error     position error compensator     feed rate regulator    

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Drivers of the development of global climate-change-mitigation technology: a patent-based decomposition

Liying SONG, Jun JING, Kerui DU, Zheming YAN

《能源前沿（英文）》 2021年 第15卷 第2期   页码 487-498 doi: 10.1007/s11708-021-0739-y

摘要： The development of the climate-change-mitigation technology has received widespread attention from both academic and policy studies. Nevertheless, very few studies have explained how and why economies contribute differently to global development. This paper decomposed the development of the global climate-change-mitigation technology, proxied by patent-based indicators, from 1996 to 2015 into several predefined factors. The results show that the worldwide surge of climate-change-mitigation-technology patents from 1996 to 2011 is driven by increased concentration on green invention, improved research intensity, and enlarged economic scale, while the falling of patent counts from 2011 to 2015 is predominantly due to less concentration on green invention. Among different climate-change-mitigation technologies, the type-specific development is attributed to different dominant factors, and the resulting priority change can reflect the shift of both global research and development (R&D) resource and market demand. Regarding regional contributions, the resulting economy-specific contributions to each driving factor can be used to design the policies to promote the development of the global climate-change-mitigation technology.

关键词： climate change mitigation     technology development     logarithmic mean Divisia index     green patents    

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Kinematic error separation on five-axis NC machine tool based on telescoping double ball bar

Min WANG, Jianzhong HU, Tao ZAN

《机械工程前沿（英文）》 2010年 第5卷 第4期   页码 431-437 doi: 10.1007/s11465-010-0110-1

摘要： The theory and algorithm of the homogeneous transformation matrix (HTM) method are applied in establishing the kinematic error model of five-axis machining tool with two-axis turntable. Based on this model, a new method for the kinematic error separation in five-axis numerical control (NC) machining tool is proposed. In this study, three types of simultaneous three-axis control motions are designed for each rotary axis to identify the deviations. In the measurement, two translational axes and one rotary axis are simultaneously controlled to keep a constant distance between the tool and the worktable. Telescoping double ball bar is used to measure the relative distance between the spindle and the worktable in the motion of NC machining tool. Finally, the value measured by telescoping double ball bar is substituted into the model to obtain kinematic error of NC machining tool. Comparison has confirmed that the proposed method is high precision and can be applied to effectively and conveniently measure the five-axis machining tool.

关键词： error modeling     error separation     telescoping double ball bar     five-axis numerical control (NC) machining tool    

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Robust ensemble of metamodels based on the hybrid error measure

《机械工程前沿（英文）》 2021年 第16卷 第3期   页码 623-634 doi: 10.1007/s11465-021-0641-7

摘要： Metamodels have been widely used as an alternative for expensive physical experiments or complex, time-consuming computational simulations to provide a fast but accurate analysis. However, challenge remains in the prior determination of the most suitable metamodel for a particular case because of the lack of information about the actual behavior of a system. In addition, existing studies on metamodels have largely restricted on solving deterministic problems (e.g., data from finite element models), whereas some real-life engineering problems (e.g., data from physical experiment) are stochastic problems with noisy data. In this work, a robust ensemble of metamodels (EMs) is proposed by combining three regression stand-alone metamodels in a weighted sum form. The weight factor is adaptively determined according to the hybrid error metric, which combines global and local error measures to improve the accuracy of the EMs. Furthermore, three typical individual metamodels that can filter noise are selected to construct the EMs to extend their application in practical engineering problems. Three well-known benchmark problems with different levels of noise and three engineering problems are used to verify the effectiveness of the proposed EMs. Results show that the proposed EMs have higher accuracy and robustness than the individual metamodels and other typical EMs in major cases.

关键词： metamodel     ensemble of metamodels     hybrid error measure     stochastic problem    

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具有新概念的运动误差及形状误差的分离法——虚位数据法

洪迈生,李自军,苏恒,叶飞帆

《中国工程科学》 2002年 第4卷 第10期   页码 48-51

摘要：

提出了一种基于信号重建的虚位数据法，用此方法，可以按需要任意选择只分离形状误差或只分离运动误差，或者任意安排分离这两类误差的先后顺序，而不必变更传统的形状误差检测-分离系统，方式灵活，使用方便。

关键词： 虚位数据     信号重建     形状误差     运动误差     误差分离技术    

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Dependence of error sensitivity of frequency on bias voltage in force-balanced micro accelerometer

Lili CHEN, Wu ZHOU

《机械工程前沿（英文）》 2013年 第8卷 第2期   页码 146-149 doi: 10.1007/s11465-013-0260-z

摘要：

To predict more precisely the frequency of force-balanced micro accelerometer with different bias voltages, the effects of bias voltages on error sensitivity of frequency is studied. The resonance frequency of accelerometer under closed loop control is derived according to its operation principle, and its error sensitivity is derived and analyzed under over etching structure according to the characteristics of Deep Reaction Ion Etching (DRIE). Based on the theoretical results, micro accelerometer is fabricated and tested to study the influences of AC bias voltage and DC bias voltage on sensitivity, respectively. Experimental results indicate that the relative errors between test data and theory data are less than 7%, and the fluctuating value of error sensitivity under the range of voltage adjustment is less than 0.01 μm . It is concluded that the error sensitivity with designed parameters of structure, circuit and process error can be used to predict the frequency of accelerometer with no need to consider the influence of bias voltage.

关键词： Micro-Electro-Mechanical Systems (MEMS)     micro accelerometer     force-balanced micro accelerometer     frequency     error sensitivity    

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全球农业发展趋势及2050 年中国农业发展展望

黄季焜,解伟,盛誉,王晓兵,王金霞,刘承芳,侯玲玲

《中国工程科学》 2022年 第24卷 第1期   页码 29-37 doi: 10.15302/J-SSCAE-2022.01.004

摘要：

本文在回顾中国农业发展历史的基础上，结合全球农业发展趋势对中国农业发展的启示，重点展望至2050 年中国农业发展趋势。研究表明，需要遵循总体经济结构转型与农村经济转型相辅相成的发展路径，提升农业劳动生产力，促进农业快速发展。至2050 年，农业GDP 占总体GDP 的比例与农业就业占总体就业的比例将逐渐趋同。中国食物自给率将从现在的95% 下降到2035 年的90% 左右，未来还会缓慢下降。高价值农产品和多功能农业的发展是未来农业增长和农民农业增收的主要增长来源。基于研究结果，提出至2050 年实现中国农业现代化的战略重点：①农业生产力提升与保障国家食物安全战略；②发挥农产品比较优势发展战略；③绿色高效高值农业发展促进战略；④农业水土资源可持续利用保障战略；⑤制度、政策、投资改革引领现代农业发展创新战略。针对主要战略提出保障措施：持续加大科技和基础设施投入，提高农业生产力；在保障粮食安全生产能力的基础上，加大优势农业及需求潜力大的农业的发展；改善市场环境、弥补市场失灵，支持高值农业发展；加快推进农业永续发展；优化配置“土地、劳动力、资金”等农业生产要素。

关键词： 全球农业发展趋势，中国农业发展，农村转型，粮食供需预测，农业现代化    

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A frequency error estimation for isogeometric analysis of Kirchhoff–Love cylindrical shells

《结构与土木工程前沿（英文）》 doi: 10.1007/s11709-023-0006-x

摘要： A frequency error estimation is presented for the isogeometric free vibration analysis of Kirchhoff–Love cylindrical shells using both quadratic and cubic basis functions. By analyzing the discrete isogeometric equations with the aid of harmonic wave assumption, the frequency error measures are rationally derived for the quadratic and cubic formulations for Kirchhoff–Love cylindrical shells. In particular, the governing relationship of the continuum frequency for Kirchhoff–Love cylindrical shells is naturally embedded into the frequency error measures without the need of explicit frequency expressions, which usually are not trivial for the shell problems. In accordance with these theoretical findings, the 2nd and 4th orders of frequency accuracy are attained for the isogeometric schemes using quadratic and cubic basis functions, respectively. Numerical results not only thoroughly verify the theoretical convergence rates of frequency solutions, but also manifest an excellent magnitude match between numerical and theoretical frequency errors for the isogeometric free vibration analysis of Kirchhoff–Love cylindrical shells.

关键词： isogeometric analysis     Kirchhoff–Love cylindrical shell     free vibration     frequency error     convergence    

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Error measurement and assemble error correction of a 3D-step-gauge

MAO Xinyong, LI Bin, SHI Hanmin, LIU Hongqi, LI Xi, LI Peigen

《机械工程前沿（英文）》 2007年 第2卷 第4期   页码 388-393 doi: 10.1007/s11465-007-0067-x

摘要： A new artifact called 3D-step-gauge consisting of a pyramid array and a compound, is proposed to calculate geometrical errors for machine tools. Only one point on each profile of the pyramid in the array is probed, and its center coordinate can be calculated. Then, the intervals of the pyramids can be transfered a length standard to measure errors. Considering the differences in the structural parameters and the location of the pyramids, a volumetric error measurement method of discrete points is presented. Furthermore, the location errors between the calibration state and the measurement state are studied and their influences on the accuracy of the position measurement are investigated on an actual machine tool. The 3D-step-gauge was tested on an actual machine tool and the measurement result shows quick assembly, convenient measurement, and high accuracy.

关键词： volumetric     pyramid     assembly     accuracy     calibration    

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Identification of thermal error in a feed system based on multi-class LS-SVM

Chao JIN, Bo WU, Youmin HU, Yao CHENG

《机械工程前沿（英文）》 2012年 第7卷 第1期   页码 47-54 doi: 10.1007/s11465-012-0307-6

摘要：

Research of thermal characteristics has been a key issue in the development of high-speed feed system. The thermal positioning error of a ball-screw is one of the most important objects to consider for high-accuracy and high-speed machine tools. The research work undertaken herein ultimately aims at the development of a comprehensive thermal error identification model with high accuracy and robust. Using multi-class least squares support vector machines (LS-SVM), the thermal positioning error of the feed system is identified with the variance and mean square value of the temperatures of supporting bearings and screw-nut as feature vector. A series of experiments were carried out on a self-made quasi high-speed feed system experimental bench HUST-FS-001 to verify the identification capacity of the presented method. The results show that the recommended model can be used to predict the thermal error of a feed system with good accuracy, which is better than the ordinary BP and RBF neural network. The work described in this paper lays a solid foundation of thermal error prediction and compensation in a feed system.

关键词： least squares support vector machine (LS-SVM)     feed system     thermal error     precision machining    

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测量与信息技术

张国雄

《中国工程科学》 2000年 第2卷 第3期   页码 62-66

摘要：

测量是获取信息的重要手段。科学研究、生产、高科技发展都离不开测量。测量技术发展的重要特点是它与信息技术的融合，这是提高测量精度、在线和动态测量、复杂参数和复杂环境下测量、智能测量的需要。这一融合贯穿始终，它包括信号调制与解调、采样与重构、信号融合、数据压缩、滤波、信号变换、时间序列分析、谱分析、数据拟合与建模、模式识别、神经网络、仿真与虚拟、误差分离、误差补偿、冗余技术、决策与智能技术等，它们互相支持。文章通过三坐标测量机误差补偿、圆度和轴系误差测量，以及大型工程的柔性坐标测量系统，介绍其在提高测量精度、优化、自标定、丢失信息自恢复、系统重组等方面的作用及其关键技术。

关键词： 测量     信息技术     误差补偿     建模     冗余技术     误差分离    

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标题 作者 时间 类型 操作

Error analysis and optimization of a 3-degree of freedom translational Parallel Kinematic Machine

null

期刊论文

SUSTAINABLE NITROGEN MANAGEMENT INDEX: DEFINITION, GLOBAL ASSESSMENT AND POTENTIAL IMPROVEMENTS

期刊论文

Theoretical prediction and validation of global horizontal solar irradiance for a tropical climate in

Sivasankari SUNDARAM,Jakka SARAT CHANDRA BABU

期刊论文

Toward energy finance market transition: Does China’s oil futures shake up global spots market?

期刊论文

Chord error constraint based integrated control strategy for contour error compensation

Tie ZHANG, Caicheng WU, Yanbiao ZOU

期刊论文

Drivers of the development of global climate-change-mitigation technology: a patent-based decomposition

Liying SONG, Jun JING, Kerui DU, Zheming YAN

期刊论文

Kinematic error separation on five-axis NC machine tool based on telescoping double ball bar

Min WANG, Jianzhong HU, Tao ZAN

期刊论文

Robust ensemble of metamodels based on the hybrid error measure

期刊论文

具有新概念的运动误差及形状误差的分离法——虚位数据法

洪迈生,李自军,苏恒,叶飞帆

期刊论文

Dependence of error sensitivity of frequency on bias voltage in force-balanced micro accelerometer

Lili CHEN, Wu ZHOU

期刊论文

全球农业发展趋势及2050 年中国农业发展展望

黄季焜,解伟,盛誉,王晓兵,王金霞,刘承芳,侯玲玲

期刊论文

A frequency error estimation for isogeometric analysis of Kirchhoff–Love cylindrical shells

期刊论文

Error measurement and assemble error correction of a 3D-step-gauge

MAO Xinyong, LI Bin, SHI Hanmin, LIU Hongqi, LI Xi, LI Peigen

期刊论文

Identification of thermal error in a feed system based on multi-class LS-SVM

Chao JIN, Bo WU, Youmin HU, Yao CHENG

期刊论文

测量与信息技术

张国雄

期刊论文