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A methodology for laser tool setters calibration and its precise mathematical model

Chinese Journal of Aeronautics 2024年第7期37卷 564-581页

作者： Tao FANG Zixi FANG ze zhong chen Zhiyong CHANG School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China Gina Cody School of Engineering and Computer Science Concordia UniversityMontrealQuebec H3G 1M8Canada Changsha Optimum CNC Corporation Changsha 410221China Institute for Aero-engine Smart Assembly of Shaanxi Province Xi’an 710072China

On-machine tool setting is a pivotal approach in achieving intelligent manufacturing,and laser tool setters have become a crucial component of smart machine *** tool setters play a crucial role in precisely measuring the dimensions of cutting tools during the part machining process,focusing on tool length and *** a measuring instrument,the positions of the laser axis of the laser tool setter need to be accurately calibrated before ***,in actual calibration scenarios,traditional calibration methods face challenges due to installation errors in the tool setter and geometric errors in the measuring *** address this issue,this study proposes a novel calibration ***,the calibration mechanism of the laser beam axis is *** on the accurate mathematical model of the laser beam and the measuring rod,and using the polygon clipping algorithm,the mathematical mechanism of the laser tool setter’s work is ***,a novel method is introduced to calculate the compensation distance between the laser beam reference point and the rod bottom center point at each moment during ***,by utilizing the kinematic chain of the tool setter calibration system,a new calibration method is developed to accurately calibrate the position of the laser beam axis in the machine tool coordinate ***,the accuracy of the calibration method is verified through simulation experiments and calibration *** method improves the calibration accuracy of the tool setter,and the mathematical model of the laser tool setter can be extended to the measurement of tools,thereby improving the precision of tool *** research significantly improves the efficient production performance of smart machine tools.

关键词： On-machine tool setting Smart machine tools Mathematical model Calibration method Laser tool sette

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Fine structure characterization of an explosively-welded GH3535/316H bimetallic plate interface

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International Journal of Minerals,Metallurgy and Materials 2021年第11期28卷 1811-1820页

作者： Jia Xiao Ming Li Jian-ping Liang Li Jiang De-jun Wang Xiang-xi Ye ze-zhong chen Na-xiu Wang Zhi-jun Li School of Materials Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Dalian National Laboratory for Clean Energy Dalian 116023China Ministry of Ecology and Environment Beijing 100135China Institute of Zhejiang University-Quzhou Quzhou 324004China

An explosion-welded technology was induced to manufacture the GH3535/316H bimetallic plates to provide a more cost-effective structural material for ultrahigh temperature,molten salt thermal storage *** microstructure of the bonding interfaces were extensively investigated by scanning electron microscopy,energy dispersive spectrometry,and an electron probe *** bonding interface possessed a periodic,wavy morphology and was adorned by peninsula-or island-like transition *** higher magnification,a matrix recrystallization region,fine grain region,columnar grain region,equiaxed grain region,and shrinkage porosity were observed in the transition zones and surrounding *** backscattered diffraction demonstrated that the strain in the recrystallization region of the GH3535 matrix and transition zone was less than the *** concentration occurred at the interface and the solidification defects in the transition *** dislocation substructure in 316H near the interface was characterized by electron channeling contrast imaging.A dislocation network was formed in the grains of *** microhardness decreased as the distance from the welding interface increased and the lowest hardness was inside the transition zone.

关键词： GH3535/316H bimetallic plate ultrahigh temperature molten salt explosive welding interface structure dislocation substructure

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The effect of bladder function on the efficacy of transurethral prostatectomy in patients with benign prostatic hyperplasia:a retrospective,single-center study

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Asian Journal of Andrology 2024年第1期26卷 112-118页

作者： Jin Li Xian-Yan-Ling Yi ze-Yu chen Bo chen Yin Huang Da-Zhou Liao Pu-ze Wang De-Hong Cao Jian-zhong Ai Liang-Ren Liu West China School of Medicine Sichuan UniversityChengdu 610041China Department of Urology Institute of UrologyWest China HospitalSichuan UniversityChengdu 610041China

We investigated the impact and predictive value of bladder function in patients with benign prostatic hyperplasia(BPH)on the efficacy of transurethral ***,imaging,and urodynamic data of patients who underwent transurethral prostatectomy at West China Hospital of Sichuan University(chengdu,China)from July 2019 to December 2021 were ***-up data included the quality of life(QoL),International Prostate Symptom Score(IPSS),and IPSS storage and voiding(IPSS-s and IPSS-v).Moreover,urinary creatinine(Cr),nerve growth factor(NGF),brain-derived neurotrophic factor(BDNF),and prostaglandin estradiol(PGE2)were measured in 30 patients with BPH and 30 healthy *** indicators were determined by subgroup analyses and receiver operating characteristic(ROC)curve *** the 313 patients with BPH included,patients with severe micturition problems had more improvements but higher micturition grades postoperatively than those with moderate ***,good bladder sensation,compliance,and detrusor contractility(Dc)were predictors of low postoperative IPSS and *** urinary concentrations of BDNF/Cr,NGF/Cr,and PGE2/Cr in patients were significantly higher than those in healthy participants(all P<***1).After evaluation,only DC was significantly related to both urinary indicators and postoperative recovery of *** with good DC,as predicted by urinary indicators,had lower IPSS and IPSS-v than those with reduced DC at the 1st month postoperatively(both P<0.05).In summary,patients with impaired bladder function had poor *** combined levels of urinary BDNF/Cr,NGF/Cr,and PGE2/Cr in patients with BPH may be valid predictors of preoperative bladderfunction and postoperative recovery.

关键词： BPH function of bladder IPSS:urodynamics

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Recent Advances in Nickel Catalyzed Carbonylative Reactions via the Insertion of Carbon Monoxide

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Chinese Journal of Chemistry 2024年第2期42卷 177-189页

作者： Xinzhou chen Gang chen zhong Lian Department of Dermatology State Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan UniversityChengduSichuan 610041China

Carbonyl compounds have attracted considerable attention due to their extensive applications in drug ***,they are important synthetic intermediates for the construction of carbon-carbon and carbon-heteroatom ***-metal-catalyzed carbonylation via the insertion of co is one of the most efficient and straightforward strategies to access carbonyl ***,most of the transition-metal-catalyzed carbonylative reactions require expensive and toxic noble-metal ***,there is a growing demand for the exploration of nickel-catalyzed carbonylative reactions via the insertion of CO due to the earth abundance and low cost of *** with the well-established palladium-catalyzed carbonylative reactions,nickel-catalyzed analogous transformations have been relatively *** is primarily because CO strongly binds to nickel,often resulting in catalyst *** recent years,some research groups have focused on using CO surrogates or NN_(2) pincer nickel catalyst to circumvent the formation of Ni(CO)_(4).Nickel-catalyzed carbonylation has been applied in the construction of carbonyl-containing compounds,such as ketones,carboxylic acids,thioesters,acyl chloride and carboxamides.

关键词： Carbonylation Nickel catalysis Carbon monoxide C1 chemistry Carbonyl-containing compounds

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Leveraging the Empirical Wavelet Transform in Combination with Convolutional LSTM Neural Networks to Enhance the Accuracy of Polar Motion Prediction

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Research in Astronomy and Astrophysics 2024年第9期24卷 214-224页

作者： Xu-Qiao Wang Lan Du zhong-Kai Zhang ze-Jun Liu Hao Xiang College of Geospatial Information Information Engineering UniversityZhengzhou 450001China Henan Industrial Technology Academy of Spatio-Temporal Big Data Zhengzhou 450046China

High-precision polar motion prediction is of great significance for deep space exploration and satellite *** motion is affected by a variety of excitation factors,and nonlinear prediction methods are more suitable for polar motion *** order to explore the effect of deep learning in polar motion *** paper proposes a combined model based on empirical wavelet transform(EWT),Convolutional Neural Networks(CNN)and Long Short Term Memory(LSTM).By training and forecasting EOP 20C04 data,the effectiveness of the algorithm is verified,and the performance of two forecasting strategies in deep learning for polar motion prediction is *** results indicate that recursive multi-step prediction performs better than direct multi-step prediction for short-term forecasts within 15 days,while direct multi-step prediction is more suitable for medium and long-term *** the 365 days forecast,the mean absolute error of EWT-CNN-LSTM in the X direction and Y direction is 18.25 mas and 15.78 mas,respectively,which is 23.5% and 16.2% higher than the accuracy of Bulletin *** results show that the algorithm has a good effect in medium and long term polar motion prediction.

关键词： data analysis methods:miscellaneous astrometry reference systems Earth

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Design and simulation investigations on charge transport layers‑free in lead‑free three absorber layer all‑perovskite solar cells

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Frontiers of Optoelectronics 2024年第2期17卷 69-85页

作者： Guangdong Li Mingxiang Xu zhong chen School of Physics Southeast UniversityNanjing 211189China

The multiple absorber layer perovskite solar cells(PSCs)with charge transport layers-free(CTLs-free)have drawn widespread research interest due to their simplified architecture and promising photoelectric *** the circumstances,the novel design of CTLs-free inversion PSCs with stable and nontoxic three absorber layers(triple Cs_(3)Bi_(2)I_(9),single MASnI_(3),double Cs_(2)TiBr_(6))as optical-harvester has been numerically simulated by utilizing wxAMPS simulation software and achieved high power conversion efficiency(PCE)of 14.8834%.This is owing to the innovative architecture of PSCs favors efficient transport and extraction of more holes and the slender band gap MASnI_(3)extends the absorption spectrum to the near-infrared periphery compared with the two absorber layers architecture of ***,the performance of the device with p-type-Cs_(3)Bi_(2)I_(9)/p-type-MASnI_(3)/n-type-Cs_(2)TiBr_(6)architecture is superior to the one with the p-type-Cs_(3)Bi_(2)I_(9)/ntype-MASnI_(3)/n-type-Cs_(2)TiBr_(6)architecture due to less carrier recombination and higher carrier life time inside the absorber *** simulation results reveal that Cs_(2)TiF_(6)double perovskite material stands out as the best ***,an excellent PCE of 21.4530%can be obtained with the thicker MASnI_(3)absorber layer thickness(0.4μm).Lastly,the highestperformance photovoltaic devices(28.6193%)can be created with the optimized perovskite doping density of around E15 cm^(3)(Cs_(3)Bi_(2)I_(9)),E18 cm^(3)(MASnI_(3)),and 1.5E19 cm^(3)(Cs_(2)TiBr_(6)).This work manifests that the proposed CTLs-free PSCs with multi-absorber layers shall be a relevant reference for forward applications in electro-optical and optoelectronic devices.

关键词： Multiple absorber layer PSCs CTLS-free·Inverted Narrow-band gap Simulation

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Side-Chain-Type Polyimide-Cu Complexes with Suppressed Activation Energy of Relaxation for Advanced High-Temperature Capacitor

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Chinese Journal of Polymer Science 2024年第8期42卷 1038-1048页

作者： Bai-Yang Zhou ze-Tong Ma Shi-Long zhong Zhen-Jie Huang Qi Guo Deng-Chong Feng zhong-Ke Yuan Shao-Lin Lu Yu-Zhao Yang cheng Wang Ding-Shan Yu Xu-Dong chen Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education Guangdong Engineering Technology Research Centre for High Performance Organic and Polymer Photoelectric Functional FilmsSchool of ChemistrySun Yat-sen UniversityGuangzhou 510275China School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China Guangdong Provincial Laboratory of Chemistry and Fine Chemical Industry Jieyang Centre Jieyang 515200China Chemistry and Chemical Engineering Guangdong Laboratory Shantou 515031China

The burgeoning growth of the new energy vehicles and aviation industry has escalated the need for energy storage capacitors capable of stable operation in harsh *** advent of metal-polyimide complexes has illuminated a novel approach for preparing tem perature-resistant ***,the general application of these metal-polyimide com plexes is impeded by the high dielectric loss and low breakdown strength,consequences of main-chain coordination and excessive metal ions ***,our study proposes a novel polyimideCu complex material(POP-Cu)predicated on side-chain-type pyridine-Cu coordination,utilizing the structural backbone PMDA-ODA of mature commercial PI(Kapton)with reliable *** to the high degree of freedom afforded by the side chain with suppressed relaxation activation energy and the long-range electron delocalization formed by d-πcoordination,the dielectric constant of this material containing merely 2.7 mol%Cu increases from 3.25(POPI)to 5.58,while maintaining a remarkably low dielectric loss of ***,this material exhibits a substantial DC breakdown strength of 436.2 MV·m^(-1)and a high energy density of 5.42 J·cm^(-3),coupled with superior mechanical and thermal *** at 150℃,it retains over 90%of its room-temperature energy density,demon strating notable dielectric stability under high *** attributes underscore its promising application for capacitors operating in harsh environments.

关键词： Dielectric performance Polyimide complexes Side-Chain-Type High-temperature capacitor

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A Bio-Inspired Integration Model of Basal Ganglia and Cerebellum for Motion Learning of a Musculoskeletal Robot

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Journal of Systems Science & Complexity 2024年第1期37卷 82-113页

作者： ZHANG Jinhan chen Jiahao zhong Shanlin QIAO Hong State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China.

It is a significant research direction for highly complex musculoskeletal robots that how to develop the ability of motion learning and *** cooperations of multiple brain regions are crucial to improving motion *** by the neural mechanisms of structures,functions,and interconnections of basal ganglia and cerebellum,a biologically inspired integration model for motor learning of musculoskeletal robots is *** on the neural characteristics of the basal ganglia,the basal ganglia actor network,which mainly simulates the dorsal striatum,outputs motion commands,and the basal ganglia critic network,which simulates the ventral striatum,estimates actionstate *** network parameters are updated using the soft actor-critic *** on the sensorimotor prediction mechanism of the cerebellum,the cerebellum network evaluates the state feature extraction quality of the basal ganglia actor network and then updates the weights of its feature *** learning method is proven to converge to the optimal ***,drawing on the mechanism of dopaminergic dynamic regulation in the basal ganglia,the adaptive adjustment of target entropy and the dopaminergic experience replay are proposed to further improve the integration model,which contributes to the exploration-exploitation trade-off of motor *** bio-inspired integration model is validated on a musculoskeletal *** results indicate that this model can effectively control the musculoskeletal robot to accomplish the motion task from random starting locations to random target positions with high precision and robustness.

关键词： Basal ganglia and cerebellum bio-inspired integration model motion learning musculoskeletal robot reinforcement learning.

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Non-monotonic behavior of jam probability and stretchedexponential distribution in pedestrian counterflow

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Chinese Physics B 2024年第9期33卷 259-266页

作者： ze-Hao chen Zhi-Xi Wu Jian-Yue Guan College of Physical Science and Technology Guangxi Normal UniversityGuilin 541004China Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu Provinceand Key Laboratory for Quantum Theory and Applications of the Ministry of EducationLanzhou UniversityLanzhou 730000China

We adopt a floor field cellular automata model to study the statistical properties of bidirectional pedestrian flow movingin a straight corridor. We introduce a game-theoretic framework to deal with the conflict of multiple pedestrians tryingto move to the same target location. By means of computer simulations, we show that the complementary cumulative distributionof the time interval between two consecutive pedestrians leaving the corridor can be fitted by a stretched exponentialdistribution, and surprisingly, the statistical properties of the two types of pedestrian flows are affected differently by theflow ratio, i.e., the ratio of the pedestrians walking toward different directions. We also find that the jam probability exhibitsa non-monotonic behavior with the flow ratio, where the worst performance arises at an intermediate flow ratio of around0.2. Our simulation results are consistent with some empirical observations, which suggest that the peculiar characteristicsof the pedestrians may attributed to the anticipation mechanism of collision avoidance.

关键词： traffic and crowd dynamics evolutionary game theory

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Micro defects formation and dynamic response analysis of steel plate of quasi-cracking area subjected to explosive load

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Defence Technology（防务技术） 2024年第1期31卷 580-593页

作者： Zheng-qing Zhou ze-chen Du Xiao Wang Hui-ling Jiang Qiang Zhou Yu-long Zhang Yu-zhe Liu Pei-ze Zhang Research Institute of Macro-Safety Science University of Science and TechnologyBeijing100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China School of Mechanical Engineering Nantong UniversityNantong226019China China North Industry Advanced Technology Generalization Institute Beijing100089China China Academy of Ordnance Science China

As the protective component,steel plate had attracted extensive attention because of frequently threats of explosive *** this paper,the evolution of microstructure and the mechanism of damage in the quasi-cracking area of steel plate subjected to explosive load were discussed and the relationships between micro defects and dynamic mechanical response were *** the explosion experiment,five observation points were selected equidistant from the quasi-cracking area of the section of the steel plate along the thickness direction,and the characteristics of micro defects at the observation points were analyzed by optical microscope(OM),scanning electron microscope(SEM) and electron backscattered diffraction(EBSD).The observation result shows that many slip bands(SBs) appeared,and the grain orientation changed obviously in the steel plate,the two were the main damage types of micro *** addition,cracks,peeling pits,grooves and other lager micro defects were appeared in the lower area of the *** stress parameters of the observation points were obtained through an effective numerical *** mechanism of damage generation and crack propagation in the quasicracking area were clarified by comparing the specific impulse of each observation point with the corresponding micro *** result shows that the generation and expansion of micro defects are related to the stress area(*** upper compression area,the neutral plane area,and the lower tension area).The micro defects gather and expand at the grain boundary,and will become macroscopic damage under the continuous action of tensile ***,the micro defects at the midpoint of the section of the steel plate in the direction away from the explosion center(*** horizontal direction) were also *** was found that the specific impulse at these positions were much smaller than that in the thickness direction,the micro defects were only SBs and a few micro cracks,and the those decrea

关键词： Explosive load Quasi-cracking area Micro defects Steel plate Dynamic response Numerical simulation

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