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New Approach for Measured Surface Localization Based on Umbilical Points

Chinese Journal of Mechanical Engineering 2017年第5期30卷 1203-1215页

作者： Xiao-Ping Xiao Ming yin Liang Heng guo-fu yin Zi-Sheng Li School of Manufacturing Science and Engineering Sichuan University Center of Engineering and Technology Southwest University of Science and Technology School of Manufacturing Science and Engineering Southwest University of Science and Technology

Measured surface localization （MSL） is one of the key essentials for the assessment of form error in pre- cision manufacturing. Currently, the researches on MSL have focused on the corresponding relation search between two surfaces, the performance improvement of localization algorithms and the uncertainty analysis of localization. However, low efficiency, limitation of localization algo- rithms and mismatch of multiple similarities of feature points with no prior are the common disadvantages for MSL. In order to match feature points quickly and fulfill MSL efficiently, this paper presents a new localization approach for measured surfaces by extracting the generic umbilics and estimating their single complex variables, describing the match methods of ambiguous relation at umbilics, presenting the initial localization process of one pair matched points, refining MSL on the basis of obtained closet points for some measured points by the improvement directed projection method. In addition, the proposed algorithm is simulated in two different types of surfaces,two different localization types and multiple similar sur- faces, also tested with the part of B-spline surface machined and bottle mould with no knowledge, finally the initial and accurate rigid body transformation matrix, localization errors between two surfaces and execution time are got. The experimental results show that the pro- posed method is feasible, more accurate in localization and high in efficiency. The proposed research can not only improve the accuracy and performance of form error assessment, but also provide an effective guideline for the integration of different types of measured surfaces.

关键词： Measured surface localization Umbilicalpoints and complex variable Similar surface patchesInitial and accurate localization

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Study on the thermally induced spindle angular errors of a five-axis CNC machine tool

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Advances in Manufacturing 2023年第1期11卷 75-92页

作者： Ji Peng Ming yin Li Cao Luo-Feng Xie Xian-Jun Wang guo-fu yin School of Mechanical Engineering Sichuan UniversityChengdu610065People’s Republic of China

Thermally induced spindle angular errors of a machine tool are important factors that affect the machining accuracy of *** is critical to develop models with good generalization abilities to control these angular thermal ***,the current studies mainly focus on the modeling of linear thermal errors,and an angular thermal error model applicable to different working conditions has rarely been ***,the formation mechanism of the angular thermal error remains to be *** this study,an analytical modeling method was proposed by analyzing the formation and propagation chain of the spindle angular thermal errors of a five-axis computer numerical control(CNC)machine *** effects of the machine tool structure and position were considered in the modeling *** angular thermal error equations were obtained by analyzing the spatial thermoelastic deformation *** analytical model of the spindle angular thermal error was established based on the geometric relation between thermal *** model parameters were identified using the trust region least squares *** results showed that the proposed analytical model exhibited good generalization ability in predicting spindle pitch angular thermal errors under different working conditions with variable spindle rotational speeds,spindle positions,and environmental temperatures in different *** average mean absolute error(MAE),root mean square error(RMSE)and R2 in twelve different experiments were 4.7μrad,5.6μrad and 0.95,*** study provides an effective method for revealing the formation mechanism and controlling the spindle angular thermal errors of a CNC machine tool.

关键词： Machine tool Angular thermal errors Thermal error modeling Analytical model

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Effects of CH_(4)/CO_(2) multi-component gas on components and properties of tight oil during CO_(2) utilization and storage: Physical experiment and composition numerical simulation

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Petroleum Science 2023年第6期20卷 3478-3487页

作者： Zhi-Hao Jia Ren-Yi Cao Bin-Yu Wang Lin-Song Cheng Jin-Chong Zhou Bao-Biao Pu fu-guo yin Ming Ma College of Petroleum Engineering China University of PetroleumBeijing102245China The Pennsylvania State University University ParkPA16802USA

An essential technology of carbon capture, utilization and storage-enhanced oil recovery (CCUS-EOR) for tight oil reservoirs is CO_(2) huff-puff followed by associated produced gas reinjection. In this paper, the effects of multi-component gas on the properties and components of tight oil are studied. First, the core displacement experiments using the CH_(4)/CO_(2) multi-component gas are conducted to determine the oil displacement efficiency under different CO_(2) and CH_(4) ratios. Then, a viscometer and a liquid density balance are used to investigate the change characteristics of oil viscosity and density after multi-component gas displacement with different CO_(2) and CH_(4) ratios. In addition, a laboratory scale numerical model is established to validate the experimental results. Finally, a composition model of multi-stage fractured horizontal well in tight oil reservoir considering nano-confinement effects is established to investigate the effects of multi-component gas on the components of produced dead oil and formation crude oil. The experimental results show that the oil displacement efficiency of multi-component gas displacement is greater than that of single-component gas displacement. The CH_(4) decreases the viscosity and density of light oil, while CO_(2) decreases the viscosity but increases the density. And the numerical simulation results show that CO_(2) extracts more heavy components from the liquid phase into the vapor phase, while CH_(4) extracts more light components from the liquid phase into the vapor phase during cyclic gas injection. The multi-component gas can extract both the light components and the heavy components from oil, and the balanced production of each component can be achieved by using multi-component gas huff-puff.

关键词： Multi-component gas Properties and components Core displacement experiment Nano-confinement numerical simulation CO_(2)utilization and storage

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Reducing the measurement errors in nonadiabatic holonomic quantum computers

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 64-70页

作者： guo-fu Xu Department of Physics Shandong University

Nonadiabatic holonomic quantum computers serve as the physical platform for nonadiabatic holonomic quantum *** quantum computation has entered the noisy intermediate-scale era, building accurate intermediate-scale nonadiabatic holonomic quantum computers is clearly necessary. Given that measurements are the sole means of extracting information, they play an indispensable role in nonadiabatic holonomic quantum computers. Accordingly, developing methods to reduce measurement errors in nonadiabatic holonomic quantum computers is of great importance. However, while much attention has been given to the research on nonadiabatic holonomic gates, the research on reducing measurement errors in nonadiabatic holonomic quantum computers is severely lacking. In this study, we propose a measurement error reduction method tailored for intermediate-scale nonadiabatic holonomic quantum computers. The reason we say this is because our method can not only reduce the measurement errors in the computer but also be useful in mitigating errors originating from nonadiabatic holonomic gates. Given these features,our method significantly advances the construction of accurate intermediate-scale nonadiabatic holonomic quantum computers.

关键词： quantum holonomy quantum computation measurement errors

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过度医疗原因解析

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医学与哲学（B） 2017年第6期38卷 7-10,14页

作者：郭福玲尹学东大连医科大学附属第一医院三部内科门诊辽宁大连116000 大连医科大学附属第一医院医务部辽宁大连116000

本文主要论述了以市场经济为主导的过度医疗,主要表现在权威欲、谋利、技术万能论三个方面,具体从医学模式所造成的过度医疗违背医学宗旨,生物医学模式隐患导致的过度医疗,精英医学与适宜技术,医学发展与传统医疗,医疗边际效应递减,谋... 详细信息

本文主要论述了以市场经济为主导的过度医疗,主要表现在权威欲、谋利、技术万能论三个方面,具体从医学模式所造成的过度医疗违背医学宗旨,生物医学模式隐患导致的过度医疗,精英医学与适宜技术,医学发展与传统医疗,医疗边际效应递减,谋利驱动,以及现代医学的技术万能论所导致的过度医疗等方面,较为详细地阐述了过度医疗违背医学宗旨的危害。过度医疗带来的社会性问题,使得医学离人文和服务对象越来越远,完全违背了医学宗旨。从而警示业界人士拒绝过度医疗。

关键词：过度医疗医学宗旨医疗市场化

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熔融沉积式燃机叶片快速熔模铸造技术研究与试验

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机床与液压 2020年第6期48卷 85-90页

作者：韩兴国刘忠崔立秀宋小辉殷国富桂林航天工业学院机械工程学院广西桂林541004 四川大学制造科学与工程学院成都710048

针对某燃机叶片叶型部分形状复杂和轮廓度精度要求高的特点,提出了一种基于熔融沉积技术的燃机叶片快速熔模铸造方法,通过基于NURBS曲线的分层截面生成算法对燃机叶片STL(stereolithography)模型进行分层,提高燃机叶片模样的轮廓度精度... 详细信息

针对某燃机叶片叶型部分形状复杂和轮廓度精度要求高的特点,提出了一种基于熔融沉积技术的燃机叶片快速熔模铸造方法,通过基于NURBS曲线的分层截面生成算法对燃机叶片STL(stereolithography)模型进行分层,提高燃机叶片模样的轮廓度精度,制订了燃机叶片快速熔模铸造工艺流程,采用三坐标测量机对燃机叶片铸件进行测量,对其两个关键截面进行型线轮廓度偏差分析与评价,结果表明:基于熔融沉积技术的快速熔模铸造燃机叶片铸件在轮廓精度方面满足要求,快速熔模铸造工艺流程合理、可行。

关键词：燃机叶片熔模铸造增材制造 NURBS 轮廓度精度

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欧盟碳边境调节机制的探析及其对中国的影响和应对

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中国标准化 2024年第3期 241-245页

作者：付国印陈晓丽广东外语外贸大学南国商学院广东贸促国际商事认证中心中国科学院广州能源研究所

欧盟碳边境调节机制(CBAM)本质上是一种新型的技术性贸易壁垒,是欧盟针对部分进口商品的碳排放向企业征收税费,该法案的实施有助于欧盟恢复经济并抢占全球气候治理的话语权及“碳排放”权的定价权,防止欧盟内部企业向排放成本更低的国... 详细信息

欧盟碳边境调节机制(CBAM)本质上是一种新型的技术性贸易壁垒,是欧盟针对部分进口商品的碳排放向企业征收税费,该法案的实施有助于欧盟恢复经济并抢占全球气候治理的话语权及“碳排放”权的定价权,防止欧盟内部企业向排放成本更低的国家进行转移,从而避免“碳泄露”。文章阐述了CBAM出台的背景、进展及意义,对CBAM实施可能对我国相关产业产生不同程度影响进行分析,建议应紧抓挑战和机遇,构建企业欧盟碳关税信息披露相关技术指南,推进可再生能源和碳交易市场机制建设。

关键词：碳边境调节机制欧盟碳关税碳泄露气候政策

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悬臂式3D打印机器人运动分析与打印实验

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机床与液压 2017年第18期45卷 70-74页

作者：韩兴国崔立秀王为庆陈海军殷国富桂林航天工业学院广西高校机器人与焊接重点实验室广西桂林541004 四川大学制造科学与工程学院成都610065

针对目前3D打印装置结构单一和打印空间小的的缺点,研制了一台悬臂式3D打印机器人。运用D-H（Denavit-Hartenberg）法建立连杆坐标系,根据齐次坐标变换,建立机器人正运动学方程,采用代数法进行逆运动学求解,通过控制各关节变量,驱动打... 详细信息

针对目前3D打印装置结构单一和打印空间小的的缺点,研制了一台悬臂式3D打印机器人。运用D-H（Denavit-Hartenberg）法建立连杆坐标系,根据齐次坐标变换,建立机器人正运动学方程,采用代数法进行逆运动学求解,通过控制各关节变量,驱动打印头在3D打印平台上按照指定轨迹实现3D打印功能,并在悬臂式3D打印机器人实验平台上进行了零件打印实验,结果表明：所设计的悬臂式3D打印机器人能够准确、有效的按照规划路径执行相应轨迹运动,表面无翘曲和变形产生,打印零件质量和精度较高。

关键词： 3D打印机器人逆运动学打印实验运动分析

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Laboratory-scale investigation of the material distribution characteristics of landslide dams in U-shaped valleys

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Journal of Mountain Science 2023年第3期20卷 688-704页

作者： JIAN fu-xian CAI Zheng-yin guo Wan-li Geotechnical Engineering Department Nanjing Hydraulic Research InstituteNanjing 210024China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing 210024China

Material distribution characteristics during sliding and depositing is particularly significative to investigate the internal structure and spatial variation of landslide dams,which are fundamentally determining the mechanical and hydraulic behavior and the susceptibility to cause dam ***,limited by longevity shortages and special geographic environments,the material distribution characteristics and their formation mechanisms are difficult to observe in the ***,an experimental apparatus modeling a landslide dam was developed in this paper,designing three sampling methods with two valley *** internal deposit characteristics,void ratio variation and relative content of the particle size range(PSR)were analyzed,and the mechanics of deposit structure were also delicately *** results indicate that granular material deposited in valley shows a structure of inverse grain size accumulation in both vertical and horizontal directions,exhibiting spatial variability of particle gradation and void *** characteristic PSR decreases from 22-30 mm in the two-dimensional state to 10-14 mm in the threedimensional *** excitation and vibration sieve are the intrinsic mechanisms of granular flow segregation,intrinsically inducing the formation of inverse grading deposit ***,spatial variability in size is mainly trig gered by segregation,whereas coarse particle content and deposition boundaries merely exacerbate the difference degree.

关键词： Landslide dam IInverse grading structure Granular flow segregation Material spatial variability Deposit characteristics

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8周运动预适应增强脂肪干细胞治疗心肌梗死大鼠的效果

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中国组织工程研究 2025年第7期29卷 1363-1370页

作者：娄国张敏付常喜江苏经贸职业技术学院江苏省南京市211168 南京旅游职业学院江苏省南京市211100 徐州工程学院体育学院江苏省徐州市221008

背景:干细胞移植是心肌梗死的崭新疗法,然而梗死区域极其恶劣的微环境造成干细胞存活率低下并导致远期疗效甚微。运动预适应是一种通过运动诱导机体产生内源性保护效应的方式,可作为心脏康复预防与治疗的新策略。目的:评估运动预适应是... 详细信息

背景:干细胞移植是心肌梗死的崭新疗法,然而梗死区域极其恶劣的微环境造成干细胞存活率低下并导致远期疗效甚微。运动预适应是一种通过运动诱导机体产生内源性保护效应的方式,可作为心脏康复预防与治疗的新策略。目的:评估运动预适应是否能够增强大鼠心肌梗死后脂肪干细胞移植的心脏保护效应,探讨血管生成在其中的作用机制。方法:6周龄雄性SD大鼠随机分为对照组、造模组、干细胞组以及干细胞运动组。利用冠状动脉闭塞术制作急性心肌梗死模型,对照组同期行假手术;干细胞运动组于造模前进行8周有氧运动,造模后30 min进行脂肪干细胞移植;干细胞组仅进行脂肪干细胞移植。干细胞移植后1 d和7 d,利用免疫印迹法测定心肌总Akt(t-Akt)、磷酸化Akt(p-Akt)、血管内皮生长因子(VEGF)、总内皮型一氧化氮合酶(t-eNOS)和磷酸化内皮型一氧化氮合酶(p-eNOS)蛋白表达量,计算p-Akt/t-Akt和p-eNOS/t-eNOS比值;4周后利用彩色多普勒超声诊断系统检测心脏结构与功能以及心肌血流量,TTC染色法检测心肌梗死面积,Masson染色法检测心肌间质胶原沉积,免疫荧光染色法测定心肌毛细血管密度,TUNEL染色法评估心肌细胞凋亡。结果与结论:(1)干细胞移植后4周:与对照组比较,造模组左心室缩短分数、左心室射血分数、心肌毛细血管密度和心肌血流量下降(P0.05);与造模组比较,干细胞组上述指标均无显著性变化(P>0.05),干细胞运动组磷酸化p-Akt蛋白表达量以及p-Akt/t-Akt比值上调(P0.05),干细胞运动组p-Akt、VEGF、p-eNOS蛋白表达量以及p-Akt/t-Akt、p-eNOS/t-eNOS比值升高(P<0.05)。结果表明:运动预适应可增强脂肪干细胞对心肌梗死大鼠心脏重塑的治疗效果,其机制与促进心肌血管生成并增加血流灌注有关。

关键词：干细胞脂肪干细胞运动预适应心肌梗死血管生成心脏重塑血流灌注

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