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Geometric error measuring,modeling,and compensation for CNC machine tools:A review

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Chinese Journal of Aeronautics 2024年第2期37卷 163-198页

作者： zhao zhang Feng JIANG Ming LUO Baohai WU Dinghua zhang Kai TANG Engineering Research Center of Advanced Manufacturing Technology for Aero Engine(Northwestern Polytechnical University) Ministry of EducationXi’an 710072China Key Laboratory of High Performance Manufacturing for Aero Engine(Northwestern Polytechnical University) Ministry of Industry and Information TechnologyXi’an 710072China Department of Mechanical and Aerospace Engineering Hong Kong University of Science and TechnologyHong KongChina

Geometric error,mainly due to imperfect geometry and dimensions of machine components,is one of the major error sources of machine tools.Considering that geometric error has significant effects on the machining quality of manufactured parts,it has been a popular topic for academic and industrial research for many years.A great deal of research work has been carried out since the 1970s for solving the problem and improving the machining accuracy.Researchers have studied how to measure,detect,model,identify,reduce,and compensate the geometric errors.This paper presents a thorough review of the latest research activities and gives an overview of the state of the art in understanding changes in machine tool performance due to geometric errors.Recent advances in measuring the geometrical errors of machine tools are summarized,and different kinds of error identification methods of translational axes and rotation axes are illustrated respectively.Besides,volumetric geometric error modeling,tracing,and compensation techniques for five-axis machine tools are emphatically introduced.Finally,research challenges in order to improve the volumetric accuracy of machine tools are also highlighted.

关键词： Error compensation Error identification Error measurement Error modeling Geometric error Machine tools

Color Image Compression and Encryption Algorithm Based on 2D Compressed Sensing and Hyperchaotic System

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Computers, Materials & Continua 2024年第2期78卷 1977-1993页

作者： Zhiqing Dong zhao zhang Hongyan Zhou Xuebo Chen School of Computer Science and Software Engineering University of Science and Technology LiaoningAnshan114051China School of Electronic and Information Engineering University of Science and Technology LiaoningAnshan114051China

With the advent of the information security era,it is necessary to guarantee the privacy,accuracy,and dependable transfer of pictures.This study presents a new approach to the encryption and compression of color images.It is predicated on 2D compressed sensing(CS)and the hyperchaotic system.First,an optimized Arnold scrambling algorithm is applied to the initial color images to ensure strong security.Then,the processed images are con-currently encrypted and compressed using 2D CS.Among them,chaotic sequences replace traditional random measurement matrices to increase the system’s security.Third,the processed images are re-encrypted using a combination of permutation and diffusion algorithms.In addition,the 2D projected gradient with an embedding decryption(2DPG-ED)algorithm is used to reconstruct images.Compared with the traditional reconstruction algorithm,the 2DPG-ED algorithm can improve security and reduce computational complexity.Furthermore,it has better robustness.The experimental outcome and the performance analysis indicate that this algorithm can withstand malicious attacks and prove the method is effective.

关键词： Image encryption image compression hyperchaotic system compressed sensing

Taming heat with tiny pressure

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The Innovation 2024年第2期5卷 70-78页

作者： Kun zhang Zhe zhang Hailong Pan Haoyu Wang Xueting zhao Ji Qi zhao zhang Ruiqi Song Chenyang Yu Biaohong Huang Xujing Li Huaican Chen Wen Yin Changlong Tan Weijin Hu Michael Wüubbenhorst Jiangshui Luo Dehong Yu Zhidong zhang Bing Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Laboratory for Soft Matter and Biophysics Department of Physics and AstronomyKU Leuven3001 LeuvenBelgium Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science Center Dongguan 523803China College of Materials Science and Engineering Sichuan UniversityChengdu 610064China School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150080China Australian Nuclear Science and Technology Organisation Lucas HeightsNSW 2234Australia

Heat is almost everywhere.Unlike electricity,which can be easily manipulated,the current ability to control heat is still highly limited owing to spontaneous thermal dissipation imposed by the second law of thermodynamics.Optical illumination and pressure have been used to switch endothermic/exothermic responses of materials via phase transitions;however,these strategies are less cost-effective and unscalable.Here,we spectroscopically demonstrate the glassy crystal state of 2-amino-2-methyl-1,3-propanediol(AMP)to realize an affordable,easily manageable approach for thermal energy recycling.The supercooled state of AMP is so sensitive to pressure that even several megapascals can induce crystallization to the ordered crystal,resulting in a substantial temperature increase of 48 K within 20 s.Furthermore,we demonstrate a proof-of-concept device capable of programable heating with an extremely high work-to-heat conversion effi-ciency of383.Such delicate and efficient tuning of heat may remarkably facilitate rational utilization of waste heat.

关键词： illumination thermal rational

Identification of reservoir types in deep carbonates based on mixedkernel machine learning using geophysical logging data

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Petroleum Science 2024年第3期21卷 1632-1648页

作者： Jin-Xiong Shi Xiang-Yuan zhao Lian-Bo Zeng Yun-zhao zhang Zheng-Ping Zhu Shao-Qun Dong Key Laboratory of Exploration Technologies for Oil and Gas Resources of the Ministry of Education Yangtze University School of Geosciences Yangtze University College of Geosciences China University of Petroleum (Beijing) Petroleum Exploration and Production Research Institute of SINOPEC School of Earth Sciences and Engineering Xi'an Shiyou University

Identification of reservoir types in deep carbonates has always been a great challenge due to complex logging responses caused by the heterogeneous scale and distribution of storage spaces. Traditional cross-plot analysis and empirical formula methods for identifying reservoir types using geophysical logging data have high uncertainty and low efficiency, which cannot accurately reflect the nonlinear relationship between reservoir types and logging data. Recently, the kernel Fisher discriminant analysis(KFD), a kernel-based machine learning technique, attracts attention in many fields because of its strong nonlinear processing ability. However, the overall performance of KFD model may be limited as a single kernel function cannot simultaneously extrapolate and interpolate well, especially for highly complex data cases. To address this issue, in this study, a mixed kernel Fisher discriminant analysis(MKFD) model was established and applied to identify reservoir types of the deep Sinian carbonates in central Sichuan Basin, China. The MKFD model was trained and tested with 453 datasets from 7 coring wells, utilizing GR,CAL, DEN, AC, CNL and RT logs as input variables. The particle swarm optimization(PSO) was adopted for hyper-parameter optimization of MKFD model. To evaluate the model performance, prediction results of MKFD were compared with those of basic-kernel based KFD, RF and SVM models. Subsequently, the built MKFD model was applied in a blind well test, and a variable importance analysis was conducted. The comparison and blind test results demonstrated that MKFD outperformed traditional KFD, RF and SVM in the identification of reservoir types, which provided higher accuracy and stronger generalization. The MKFD can therefore be a reliable method for identifying reservoir types of deep carbonates.

关键词： Reservoir type identification Geophysical logging data Kernel Fisher discriminant analysis Mixed kernel function Deep carbonates

Experimental Investigation on Flow Pattern and Bubble Behavior during Subcooled Flow Boiling of R1233zd(E)in Parallel Channels

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Journal of Thermal Science 2023年第6期32卷 2374-2385页

作者： FANG Yidong zhang zhao XU Dan WANG Yuchen YANG Huinan HUANG Yuqi School of Energy and Power Engineering University of Shanghai for Science and TechnologyShanghai200093China Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering Shanghai200093China Key Laboratory of Clean Energy and Carbon Neutrality of Zhejiang Province Jiaxing Research InstituteZhejiang UniversityJiaxing314031China Key Laboratory of Smart Thermal Management Science&Technology for Vehicles of Zhejiang Province Taizhou317200China

In this study,the flow pattern and bubble behavior of R1233zd(E)during subcooled flow boiling in parallel channels are experimentally investigated with visualization and thermal measurement.The test section is composed of 21 rectangular mini channels with the hydraulic diameter of 1.5 mm and the length of 140 mm.Bubbly flow,slug flow,churn flow and wavy-annular flow occur in sequence with the increase of vapor quality,while transient flow pattern transition process involving multiple flow patterns are also captured.The distribution of flow pattern is non-synchronized and axial-asymmetric,with earlier flow pattern transitions observed in peripheral channels away from the center axis.The initial nucleate site in each channel also show a random and axial-asymmetric distribution,while faster bubble growth can be noted in some channel under the comprehensive effects of liquid evaporation and bubble coalescence.The variation of heat transfer coefficient is correspondence to the flow pattern transition,showing different trends along the flow direction.The increase of mass flux can lead to delayed flow pattern transition and variation of heat transfer coefficient.In addition,higher heat transfer coefficient can be noted in channels away from the center axis.

关键词： flow boiling flow pattern bubble behavior parallel channel visualization

温州中心片污水处理厂深基坑工程的设计与施工

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中国给水排水 2024年第10期40卷 114-120页

作者：赵璋温州市城市建设开发项目前期研究中心浙江温州325000

温州市中心片污水处理厂基坑支护工程设计及施工面临很多技术难题,实施过程中对整个基坑支护设计、施工全过程进行了精细化研究。采用数值反分析手段建立考虑盆边留土作用的基坑支护结构分析计算参数m的取值公式;根据开挖深度、土体性... 详细信息

温州市中心片污水处理厂基坑支护工程设计及施工面临很多技术难题,实施过程中对整个基坑支护设计、施工全过程进行了精细化研究。采用数值反分析手段建立考虑盆边留土作用的基坑支护结构分析计算参数m的取值公式;根据开挖深度、土体性质、周边情况综合比选基坑支护形式,优化施工方案,并着重对高压旋喷预应力锚杆工艺中的斜向引孔、锚杆安装、成桩等工序进行详细方案设计;针对土方开挖及运输工程制定了完善详细的施工组织计划;通过不断优化全过程方案,在保证安全可靠的前提下,节约了大量投资,取得了较好的经济效益。

关键词：半地下污水处理厂深基坑支护预应力锚杆土方开挖施工组织施工优化

Nonlinearly induced entanglement in dissipatively coupled optomechanical system

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Chinese Physics B 2024年第6期33卷 255-260页

作者：杨文全冷轩程泂张闻钊 Department of Physics Ningbo UniversityNingbo 315211China

Nonlinearly induced steady-state photon–phonon entanglement of a dissipative coupled system is studied in the bistable regime. Quantum dynamical characteristics are analysed by solving the mean-field and fluctuation equations of the system. It is shown that dissipative coupling can induce bistable behaviour for the effective dissipation of the system.Under suitable parameters, one of the steady states significantly reduces the dissipative effect of the system. Consequently,a larger steady-state entanglement can be achieved compared to linear dynamics. Furthermore, the experimental feasibility of the parameters is analysed. Our results provide a new perspective for the implementation of steady-state optomechanical entanglement.

关键词： entanglement optomechanical system dissipatively coupling

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具有双储层结构的动态误差补偿回声状态网络

控制理论与应用 2024年第3期41卷 385-395页

作者：张昭昭朱应钦余文西安科技大学计算机科学与计算学院陕西西安710054 墨西哥国立理工大学高级研究中心(CINVESTAV)自动化研究所墨西哥城07360

针对传统回声状态网络难以有效应对高阶非线性复杂模型问题,本文在理论分析的基础上提出了一种双储层结构的误差补偿回声状态网络,并设计了该网络的学习算法.该网络由计算层和补偿层构成,计算层主要承担拟合任务,补偿层则作为状态跟随器... 详细信息

针对传统回声状态网络难以有效应对高阶非线性复杂模型问题,本文在理论分析的基础上提出了一种双储层结构的误差补偿回声状态网络,并设计了该网络的学习算法.该网络由计算层和补偿层构成,计算层主要承担拟合任务,补偿层则作为状态跟随器,实时补偿由于计算层对期望方差估计不足而导致的幅值偏差.对多阶振荡器和真实高阶非线性数据集的实验结果表明,本文所提网络结构较常规网络具有更高的稳定性和泛化性能,尤其对高阶非线性复杂模型的预测精度大幅度提升.

关键词：回声状态网络高阶非线性复杂模型补偿回声状态网络多阶振荡器

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石油污染土壤微生物修复技术及机理研究进展

应用化工 2024年第2期53卷 414-418页

作者：张钊河北工程大学能源与环境工程学院河北邯郸056038

综述了环境微生物技术在石油污染土壤修复中的应用方法,介绍了人为干预提高石油降解微生物治理油污土壤的原位和异位修复技术和微生物去除石油组分的作用机理。针对微生物修复的研究热点多为石油降解微生物的选取及多种微生物的复合菌... 详细信息

综述了环境微生物技术在石油污染土壤修复中的应用方法,介绍了人为干预提高石油降解微生物治理油污土壤的原位和异位修复技术和微生物去除石油组分的作用机理。针对微生物修复的研究热点多为石油降解微生物的选取及多种微生物的复合菌对石油组分的去除效果,但对微生物技术的实际应用和机理研究相对较少。提出了未来微生物技术修复石油污染土壤的研究和发展方向,包括特定材料对微生物的固定化、利用宏组学与示踪技术进一步明确微生物的降解机理和质粒拼接手段构建高效基因工程菌。

关键词：石油污染土壤微生物修复吸收转运机理功能基因