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Pre-Compensation for Continuous-Path Running Trajectory Error in High-Speed Machining of Parts with Varied Curvature Features

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Chinese Journal of Mechanical Engineering 2017年第1期30卷 37-45页

作者： JIA Zhenyuan SONG Dening MA Jianwei gao yuanyuan Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education Dalian University of TechnologyDalian 116024China

Parts with varied curvature features play increasingly critical roles in engineering, and are often machined under high-speed continuous-path running mode to ensure the machining efficiency. However, the continuous-path running trajectory error is significant during high-feed-speed machining, which seriously restricts the machining precision for such parts with varied curvature features. In order to reduce the continuous-path running trajectory error without sacrificing the machining efficiency, a pre-compensation method for the trajectory error is proposed. Based on the formation mechanism of the continuous-path running trajectory error analyzed, this error is estimated in advance by approximating the desired toolpath with spline curves. Then, an iterative error pre-compensation method is presented. By machining with the regenerated toolpath after pre-compensation instead of the uncompensated toolpath, the continuous-path running trajectory error can be effectively decreased without the reduction of the feed speed. To demonstrate the feasibility of the proposed pre-compensation method, a heart curve toolpath that possesses varied curvature features is employed. Experimental results indicate that compared with the uncompensated processing trajectory, the maximum and average machining errors for the pre-compensated processing trajectory are reduced by 67.19% and 82.30%, respectively. An easy to implement solution for high efficiency and high precision machining of the parts with varied curvature features is provided.

关键词： trajectory error dynamic error pre-compensation continuous-path running high-feed-speed machining,parts with varied curvature features

维普期刊数据库

Land Use Allocation Based on Interval Multi-objective Linear Programming Model: A Case Study of Pi County in Sichuan Province

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Chinese Geographical Science 2010年第2期20卷 176-183页

作者： WANG Hongrui gao yuanyuan LIU Qiong SONG Jinxi College of Water Science Beijing Normal University Beijing 100875 China Key Laboratory for Water and Sediment Science Ministry of Education Beijing 100875 China Department of Environmental Sciences Northwest University Xi＇an 710127 China

Adjusting and optimizing land use structure is one of the essential approaches to solve the conflict between land supply and demand. In this study,an uncertain interval multi-objective linear programming model was established and applied to analyzing the suitability of land use structure in Pi County of Sichuan Province. An adjustment scheme for optimizing land use structure was proposed on the basis of development planning drawn up by the local government. The results are summarized as follows: 1) the optimal adjustment scope for cropland area ranges from 27 976.75 ha to 31 029.08 ha,and the current area is less than the lower limit of the scope; 2) the optimal adjustment scope for garden land area ranges from 4 736.49 ha to 12 967.11 ha,and the current area is less than the lower limit; 3) the optimal adjustment scope for construction land ranges from 7 761.95 ha to 10 393.18 ha,and the current area is greater than the upper limit; 4) the optimal adjustment scope for industry and mining land ranges from 557.29 ha to 693.54 ha,and the current area exceeds the upper limit; and 5) the areas of forest land,grassland and other agricultural land are within the optimal adjustment scope. In order to maximize comprehensive benefit with the limited resources and the demand of sustainable development,the areas of cropland and garden land are supposed to be expanded properly,while the construction land should be controlled and reduced gradually,and the forest land and other agricultural land can be maintained at the current level in short period.

关键词： land use structure optimization land supply and demand balance interval multi-objective planning uncertainty

维普期刊数据库

Facile one-pot emulsion/sol-gel method for preparing wrinkled silica microspheres

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Particuology 2021年第3期19卷 33-42页

作者： Yuning Hu Dongxia Hao Fangling Gong yuanyuan gao Xingran Yan Guanghui Ma State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of ScienceBeijing 100190China University of Chinese Academy of Sciences Beijing 100190China

The present manuscript describes a facile and versatile method for preparing uniform wrinkled silica microspheres with diameters of tens of *** method comprises a one-pot emulsion/sol-gel method using silica precursors of organosilane and *** controlling the sol-to-gel transition of the silica precursors,a series of silica microspheres based on uniform emulsion droplets was synthesized by membrane *** silica microspheres had a variety of surface morphologies ranging from smooth,maze-like wrinkles to polygon-like *** was possible to alter the surface morphologies of the microspheres by controlling the amount of organosilane in the dispersed phase and the amount of ammonia catalyst in the continuous phase of the *** grooves on the wrinkled microspheres were able to trap polymer nanoparticles of matching size,thereby demonstrating the potential usefulness of the microspheres in separation science and drug delivery.

关键词： Wrinkled silica microsphere Membrane emulsification Emulsion/sol-gel method

Preceding Vehicle Distance Computation Based on Dark Prior 36

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Preceding Vehicle Distance Computation Based on Dark Prior

Photolysis and Cycloaddition Reactivity of Diferrocenyl Substituted Cyclopentadienone

第36届中国控制会议

作者： Hongjun Song yuanyuan gao School of Information Engineering Zhejiang A & F University Zhejiang Provincial Key Laboratory of Forestry Intelligent Monitoring and Information Technology Zhejiang A & F University

ISBN: (纸本)9781538629185

This paper presents a monocular vision system for the detection and distance computation of preceding vehicles under foggy weather *** is divided in three major ***,adaboost algorithm is used to detect vehicles in front of the host ***,these vehicles will be tracked by camshaft algorithm;the initial points for camshift algorithm are the centers of the preceding vehicles detected by adaboost *** the distance between these vehicles and the host vehicle will be calculated based on dark prior algorithm and monocular ***,experimental results are given.90%of preceding vehicles are detected *** data for three preceding vehicles are listed in the form of graphic and *** distance between these vehicles and the host vehicle calculated by our algorithm is close to the real distance observed by manual *** results verify the effectiveness of the algorithm.

关键词： Monocular vision system Dark prior Camshift Vehicle detection Vehicle traction Aadaboost

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Chemical Research in Chinese Universities 2016年第5期32卷 775-780页

作者： ZHANG Xiaoyong HAN Limin gao yuanyuan SHI Jiale SUO Quanling Chemical Engineering College Inner Mongolia University of Technology Hohhot 010051 P. R. China Department of Chemistry Baotou Teacher's College Baotou 014030 P. R. China

The photolysis results of new diferrocenyl substituted cyclopentadienone（3） show that sunlight and air play an important role in the decomposition of compound 3, and two new compounds, 2-cyclopentenone（4） and a-pyrone（5）, were obtained via photolysis of compound 3. The photolysis process was investigated by IH NMR, and a plausible mechanism for the formation of compound 5 was deduced. The cycloaddition reactions of substituted cyclopentadienones（3, 7, 9） with maleimide gave substituted imides 8, 10, 11, 12 and an unprecedented diferrocenyl substituted 1H-pyrrol-3（2H）-one derivative 13, respectively. The structures of compounds 4, 5, 8, 10, 11, 12 and 13 were confirmed by X-ray single crystal diffraction analysis technique.

关键词： Cyclopentadienone Reactivity Photolysis Cycloaddition Crystal structure

Reactivity of Organolithium Reagents to 2,3,4,5-Tetraphenylcyclopentadienone and Crystal Structures of Addition Products

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Chemical Research in Chinese Universities 2015年第5期31卷 736-741页

作者： ZHANG Xiaoyong HAN Limin ZHU Ning gao yuanyuan SUO Quanling Chemical Engineering College Inner Mongolia University of Technology Hohhot 010051 P. R. China Department of Chemistry Baotou Teacher's College Baotou 014030 P. R. China

The conjugate addition reactions of four organolithium reagents to 2,3,4,5-tetraphenylcyclopentadienone （tetracyclone） were investigated to reveal the reactivity of organolithium reagents to tetracyclone. The results show that 1,2-addition products 2,3,4,5-tetraphenyl-1-（2-thienyl）-2,4-cyclopentadien-l-ol（1）, 1-n-butyl-2,3,4,5-tetraphenyl- 2,4-cyclopentadien-l-ol（2） and 1,2,3,4,5-pentaphenyl-2,4-cyclopentadien-1-ol（3） were synthesized in excellent yields while tetracyclone reacted with 2-thienyllithium, n-butyllithium and phenyllithium, respectively. Interestingly, three 1,2-, 1,4- and 1,6-addition isomers 1-tert-butyl-2,3,4,5-tetraphenyl-2,4-cyclopentadien-1-ol（4）, 4-tert-butyl-2,3,4,5- tetraphenyl-2-cyclopenten-1-one（5） and 2-tert-butyl-2,3,4,5-tetraphenyl-3-cyclopenten-1-one（6）, were simultaneously obtained by the conjugate addition reaction of tert-butyllithium with larger steric hindrance to tetracyclone. Compounds 1-6 were characterized by ^1H and ^13C NMR spectra, Fourier transform infrared（FTIR） spectra and mass spectra（MS）. The crystal and molecular structures of compounds 1, 2 and isomers 5, 6 were determined by X-ray single crystal diffraction technique. The results imply that the steric hindrance of tert-butyllithium probably play a key role in controlling the conjugate addition reaction. The conjugate addition mechanism of organolithium reagents to tetracyclone was proposed.

关键词： Conjugate addition reaction 2,3,4,5-Tetraphenylcyclopentadienone Organolithium reagent Steric hindrance

Optimal Weighting Method for Reducing Digital Satellite TV Differential Timing Error

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Chinese Journal of Electronics 2020年第2期29卷 322-326页

作者： WANG Shanhe HUA Yu XIANG Yu HUANG Changjiang gao yuanyuan ZHAO Xian National Time Service Center Chinese Academy of Sciences University of Chinese Academy of Sciences

We illustrate the principle of Digital satellite TV differential timing(DSTVDT) and propose an optimal weighting method that reduces the timing error introduced by satellite ephemeris error. A mathematical formula for the timing error introduced by satellite ephemeris error is derived and analyzed. On the basis of the derived formula, the proposed optimal weighting method based on multi-base stations is presented. The results of data simulation and experiments show that when the proposed method is applied, for a satellite ephemeris error of 10 km, the ephemeris-introduced timing error is less than 10 ns, which is important for improving accuracy and stability of the timing system.

关键词： Digital satellite TV differential timing(DSTVDT) Satellite ephemeris error Timing accuracy Optimal weighting method

Examining Chinese EFL Postgraduates’ Motivational Regulation Strategies

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同方期刊数据库

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Frontiers of Education in China 2020年第2期15卷 250-278页

作者： YAN Chunmei gao yuanyuan HE Chuanjun School of Foreign Languages Central China Normal UniversityWuhan 430079China Jun’an Secondary School Foshan 528000China

This study set out to explore non-English major postgraduates’use of motivational regulation strategies in English *** for this study were 156 Chinese postgraduates studying in a national teacher education university in central China.A self-reported questionnaire and individual semi-structured interviews were complementarily employed to gather *** non-English major postgraduates were found to have adopted ten types of strategy to regulate their motivation for learning English,but that these strategies were used *** was also found that despite the general absence of significant difference,the few that could be ascertained were associated with gender,specialty,and *** results suggest a need to provide motivation regulation strategies training,and nurture students’intrinsic English learning motivation through curricular,instructional and assessment reforms.

关键词： Chinese non-English major postgraduates English as a foreign language(EFL) motivational regulation strategies learner differences

Heat exposure promotes apoptosis and pyroptosis in Sertoli cells

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BIOCELL 2023年第1期47卷 155-164页

作者： CHEN WANG CHAOFAN HE yuanyuan gao KAIXIAN WANG MENG LIANG School of Life Science Bengbu Medical CollegeBengbu233030China

Heat stress is an important influence on the male reproductive ***,the effects of heat stress on genes or pathways related to the reproductive system of male mice were experimentally explored in this paper to further determine the effects of heat stimulation on ***,models of heat-exposed mouse testicular tissue and heatexcited cells were successfully *** scorched vesicles were found after heat excitation of testis supporting cells,testicular mesenchymal(TM4)*** blot,in situ terminal deoxynucleotide transferase dUTP Nick end labeling(TUNEL)and transmission electron microscopy showed that membrane rupture,mitochondrial damage and autophagic vesicles occurred in TM4 cells after thermal *** N-segment fragment of the associated protein shear was increased,and the TUNEL result was *** conclusion,thermal excitation induced apoptosis and scorch death in TM4 ***,the Hippo pathway and apoptosis-related pathway were significantly enriched after heat stimulation in mouse testis,and the scorch death effect in TM4 cells was induced by heat excitation.

关键词： Heat shock Hippo pathway Sertoli cells Apoptosis Pyroptosis