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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

Trajectory of COVID-19 response and management strategy in China:scientific rationale driven strategy adjustments

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Frontiers of Medicine 2024年第1期18卷 19-30页

作者： Zeyu zhang Yue Yan Lina zhao Yizhou Bian Ning zhao You Wu Dahai zhao Zongjiu zhang Institute for Hospital Management Tsinghua UniversityBeijing100084China School of Medicine Tsinghua UniversityBeijing100084China School of International and Public Affairs Shanghai Jiao Tong UniversityShanghai200030China Yale University-Shanghai Jiao Tong University Joint Center for Health Policy Shanghai Jiao Tong UniversityShanghai200030China

The pneumonia caused by novel coronavirus SARS-CoV-2 infection in early December 2019,which was later named coronavirus disease 2019(COVID-19)by the World Health Organization(WHO),rapidly spread across the world.China has made extraordinary efforts to this unprecedented pandemic,put its response and control at a very high level of infectious disease management(Category B but with measures for Category A),given top priority to the people and their lives,and balanced the pandemic control and socio-economic development.After more than three years’fighting against this disease,China downgraded the management of COVID-19 to Category B infectious disease on January 8,2023 and the WHO declared the end of public health emergency on May 5,2023.However,the ending of pandemic does not mean that the disease is no longer a health threat.Experiences against COVID-19 from China and the whole world should be learned to prepare well for the future public health emergencies.This article gives a systematic review of the trajectory of COVID-19 development in China,summarizes the critical policy arrangements and provides evidence for the adjustment during policy making process,so as to share experiences with international community and contribute to the global health for all humanity.

关键词： COVID-19 public health response and control strategy science-based policy making

Frequency Domain Fatigue Evaluation on SCR Girth-Weld Based on Structural Stress

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China Ocean Engineering 2024年第2期38卷 255-270页

作者： zhang Long zhao Tian-feng College of Safety and Ocean Engineering China University of Petroleum(Beijing)Beijing 102249China

The Steel Catenary Riser(SCR)is a vital component for transporting oil and gas from the seabed to the floating platform.The harsh environmental conditions and complex platform motion make the SCR’s girth-weld prone to fatigue failure.The structural stress fatigue theory and Master S-N curve method provide accurate predictions for the fatigue damage on the welded joints,which demonstrate significant potential and compatibility in multi-axial and random fatigue evaluation.Here,we propose a new frequency fatigue model subjected to welded joints of SCR under multiaxial stress,which fully integrates the mesh-insensitive structural stress and frequency domain random process and transforms the conventional welding fatigue technique of SCR into a spectrum analysis technique utilizing structural stress.Besides,a full-scale FE model of SCR with welds is established to obtain the modal structural stress of the girth weld and the frequency response function(FRF)of modal coordinate,and a biaxial fatigue evaluation about the girth weld of the SCR can be achieved by taking the effects of multi-load correlation and pipe-soil interaction into account.The research results indicate that the frequency-domain fatigue results are aligned with the time-domain results,meeting the fatigue evaluation requirements of the SCR.

关键词： SCR girth weld random vibration self(cross)power spectrum structural stress method biaxial fatigue damage

Effect of oxide interactions on chromium speciation transformation during simulated municipal solid waste incineration

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Journal of Environmental Sciences 2024年第8期142卷 11-20页

作者： Guodong zhao Chong Tian Peidong Wu Xuguang zhang Zhikang Wang Xiaoxiang Chen Zhuo Xiong Yongchun zhao Junying zhang State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China National Environmental Protection Engineering Technology Center for Trace Elements Pollution Control and Low Carbon Utilization of Coal Huazhong University of Science and TechnologyWuhan 430074China School of Environmental Engineering Wuhan Textile UniversityWuhan 430200China

Chromium released during municipal solid waste incineration(MSWI)is toxic and carcinogenic.The removal of chromium from simulated MSWI flue gas by four sorbents(CaO,bamboo charcoal(BC),powdered activated carbon(PAC),and Al_(2)O_(3))and the effects of four oxides(SiO_(2),Al_(2)O_(3),Fe_(2)O_(3),and CaO)on chromium speciation transformationwere investigated.The results showed that the removal rates of total Cr by the four sorbents were Al_(2)O_(3)

关键词： Cr(Ⅵ)reduction Cr(Ⅲ)oxidation Alkali oxides Acidic oxides Municipal solid waste incineration

Circulating RNA ZFR promotes hepatocellular carcinoma cell proliferation and epithelial-mesenchymal transition process through miR-624-3p/WEE1 axis

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 52-63页

作者： Li zhang Sai He Hao Guan Yao zhao Di zhang Department of General Surgery the Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710004China Department of Breast Cancer Shaanxi Provincial Cancer HospitalXi’an 710000China

Background:Hepatocellular carcinoma(HCC),the most common type of primary liver cancer,is the fourth leading cause of cancer-related deaths worldwide.Previous evidence shows that the expression of circulating RNA ZFR(circZFR)is upregulated in HCC tissues.However,the molecular mechanism of circZFR in HCC is unclear.Methods:Quantitative reverse transcriptase polymerase chain reaction(qRT-PCR)was employed to detect the expression of circZFR,microRNA-624-3p(miR-624-3p)and WEE1 in HCC tissues and cells.RNase R assay and actinomycin D treatment assay were used to analyze the characteristics of circZFR.For functional analysis,the capacities of colony formation,cell proliferation,cell apoptosis,migration and invasion were assessed by colony formation assay,5-ethynyl-2-deoxyuridine(EdU)assay,flow cytometry assay and transwell assay.Western blot was used to examine the protein levels of WEE1 and epithelial-mesenchymal transition(EMT)-related proteins.The interactions between miR-624-3p and circZFR or WEE1 were validated by dual-luciferase reporter assay and RNA immunoprecipitation(RIP)assay.Xenograft models were established to determine the role of circZFR in vivo.Results:circZFR and WEE1 were upregulated,while miR-624-3p expression was reduced in HCC tissues and cells.circZFR could sponge miR-624-3p,and WEE1 was a downstream gene of miR-624-3p.Knockdown of circZFR significantly reduced the malignant behaviors of HCC and that co-transfection with miR624-3p inhibitor restored this change.Overexpression of WEE1 abolished the inhibitory effect of miR624-3p mimic on HCC cells.Mechanistically,circZFR acted as a competitive endogenous RNA(ceRNA)to regulate WEE1 expression by targeting miR-624-3p.Furthermore,in vivo studies have illustrated that circZFR knockdown inhibited tumor growth.Conclusions:circZFR knockdown reduced HCC cell proliferation,migration and invasion and promoted apoptosis by regulating the miR-624-3p/WEE1 axis,suggesting that the circZFR/miR-624-3p/WEE1 axis might be a potential target for HCC treatment.

关键词： Hepatocellular carcinoma circZFR miR-624-3p WEE1 Liver cancer

Exercise-with-melatonin therapy improves sleep disorder and motor dysfunction in a rat model of ischemic stroke

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Neural Regeneration Research 2024年第6期19卷 1336-1343页

作者： Haitao zhao Tong zhang Haojie zhang Yunlei Wang Lingna Cheng School of Rehabilitation Medicine Capital Medical University Department of Neurological Rehabilitation Beijing Bo'ai Hospital China Rehabilitation Research Center 3. School of Rehabilitation Medicine University of Health and Rehabilitation Sciences 4. Laboratory of Brain Injury Repair and Rehabilitation China Rehabilitation Science Institute

Exercise-with-melatonin therapy has complementary and synergistic effects on spinal cord injury and Alzheimer’s disease, but its effect on stroke is still poorly understood. In this study, we established a rat model of ischemic stroke by occluding the middle cerebral artery for 60 minutes. We treated the rats with exercise and melatonin therapy for 7 consecutive days. Results showed that exercise-with-melatonin therapy significantly prolonged sleep duration in the model rats, increased delta power values, and regularized delta power rhythm. Additionally, exercise-with-melatonin therapy improved coordination, endurance, and grip strength, as well as learning and memory abilities. At the same time, it led to higher hippocampal CA1 neuron activity and postsynaptic density thickness and lower expression of glutamate receptor 2 than did exercise or melatonin therapy alone. These findings suggest that exercise-withmelatonin therapy can alleviate sleep disorder and motor dysfunction by increasing glutamate receptor 2 protein expression and regulating hippocampal CA1 synaptic plasticity.

关键词： exercise glutamate receptor 2 hippocampus ischemic stroke learning melatonin memory sleep disorder synaptic plasticity

Integration of Multiple Spectral Data via a Logistic Regression Algorithm for Detection of Crop Residue Burned Areas:A Case Study of Songnen Plain,Northeast China

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Chinese Geographical Science 2024年第3期34卷 548-563页

作者： zhang Sumei zhang Yuan zhao Hongmei College of Mining and Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China

The burning of crop residues in fields is a significant global biomass burning activity which is a key element of the terrestrial carbon cycle,and an important source of atmospheric trace gasses and aerosols.Accurate estimation of cropland burned area is both crucial and challenging,especially for the small and fragmented burned scars in China.Here we developed an automated burned area mapping algorithm that was implemented using Sentinel-2 Multi Spectral Instrument(MSI)data and its effectiveness was tested taking Songnen Plain,Northeast China as a case using satellite image of 2020.We employed a logistic regression method for integrating multiple spectral data into a synthetic indicator,and compared the results with manually interpreted burned area reference maps and the Moderate-Resolution Imaging Spectroradiometer(MODIS)MCD64A1 burned area product.The overall accuracy of the single variable logistic regression was 77.38%to 86.90%and 73.47%to 97.14%for the 52TCQ and 51TYM cases,respectively.In comparison,the accuracy of the burned area map was improved to 87.14%and 98.33%for the 52TCQ and 51TYM cases,respectively by multiple variable logistic regression of Sentind-2 images.The balance of omission error and commission error was also improved.The integration of multiple spectral data combined with a logistic regression method proves to be effective for burned area detection,offering a highly automated process with an automatic threshold determination mechanism.This method exhibits excellent extensibility and flexibility taking the image tile as the operating unit.It is suitable for burned area detection at a regional scale and can also be implemented with other satellite data.

关键词： crop residue burning burned area Sentinel-2 Multi Spectral Instrument(MSI) logistic regression Songnen Plain,China