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Chinese Journal of Mechanical Engineering 2024年第2期37卷 264-282页

作者： xin.pan Xiancheng Zhang Zhinong Jiang Guangfu Bin Beijing Key Laboratory of Health Monitoring and Self-recovery for High-End Mechanical Equipment College of Mechanical and Electrical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Key Laboratory of Engine Health Monitoring-Control and Networking(Ministry of Education) College of Mechanical and Electrical EngineeringBeijing University of Chemical TechnologyBeijing 100029China College of Mechanical Engineering Hunan University of Science and TechnologyXiangtan 411201China

The co-frequency vibration fault is one of the common faults in the operation of rotating equipment,and realizing the real-time diagnosis of the co-frequency vibration fault is of great significance for monitoring the health state and carrying out vibration suppression of the *** engineering scenarios,co-frequency vibration faults are highlighted by rotational frequency and are difficult to identify,and existing intelligent methods require more hardware conditions and are exclusively ***,Lightweight-convolutional neural networks(LW-CNN)algorithm is proposed in this paper to achieve real-time fault *** critical parameters are discussed and verified by simulated and experimental signals for the sliding window data augmentation *** on LW-CNN and data augmentation,the real-time intelligent diagnosis of co-frequency is ***,a real-time detection method of fault diagnosis algorithm is proposed for data acquisition to fault *** is verified by experiments that the LW-CNN and sliding window methods are used with high accuracy and real-time performance.

关键词： Co-frequency vibration Real-time diagnosis LW-CNN Data augmentation

Flow Field Simulation and Parameter Analysis of Hydraulic Unbalanced Bionic Self-recovery Actuator for Rotary Equipment

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Journal of Bionic Engineering 2024年第1期21卷 325-343页

作者： Wei Li xin.pan Dehong Ge Jinji Gao Key Laboratory of Engine Health Monitoring-Control and Networking of Ministry of Education Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of High-End Mechanical Equipment Health Monitoring and Self-Recovery Beijing University of Chemical TechnologyBeijing 100029China

The rotor is the most important component of rotating machinery,and the vibration produced by its mass unbalance has a serious influence on the secure and steady operation of the machine,so an effective online suppression technology is urgently needed.A new hydraulic unbalanced bionic self-recovery system is introduced,imitating the way of manually repairing faulty *** accomplish the effect of actuator mass redistribution,the technology employs pressurized air to drive the quantitative transfer of liquid in the reservoir cavity at opposite *** can complete the online adjustment of the equipment's balancing state and suppress the unbalanced vibration of equipment in real time,which gives the equipment the ability to maintain an autonomous health state and improve equipment *** composition and working principle of the system are introduced in detail,and the key performance parameters,such as the minimum running speed and the balancing liquid transfer speed,are analyzed *** fluid-solid coupling model of the actuator was established,and the two-phase flow from inside the hydraulic unbalanced bionic self-recovery actuator was simulated under multiple working conditions and the performance parameters were quantitatively analyzed.A balancing simulation test bed was built,and its effectiveness was verified by performance parameter tests and unbalanced bionic self-recovery *** experimental results show that the mass distribution adjustment of the balancing disk can be achieved using different viscosity balancing liquid,and the response of liquid viscosity 10 cSt is faster than that of liquid viscosity 100 cSt in the process of balancing liquid transfer,and the time is reduced by more than 75%;the system can reduce the simulated rotor amplitude from 18.3μm to 10.6μm online in real time,which provides technical support for the subsequent development of a new generation of bionic intelligent equipment.

关键词： Engineering self-recovery-Bionics Simulation analysis Self-recovery regulation

Intelligent Diagnosis Method for Typical Co-frequency Vibration Faults of Rotating Machinery Based on SAE and Ensembled ResNet-SVM

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 215-230页

作者： Xiancheng Zhang xin.pan Hao Zeng Haofu Zhou Beijing Key Laboratoryof Health Monitoring and Self-recovery for High-end Mechanical Equipment Beijing University of Chemical TechnologyBeijing 100029China Engineering Research Center of Chemical Safety(Ministry of Education) Beijing University of Chemical TechnologyBeijing 100029China Engineering Management Department of China Three Gorges New Energy(Group)Co. Ltd.Beijing 101199China

Intelligent fault diagnosis is an important method in rotating machinery fault diagnosis and equipment health *** deal with co-frequency vibration faults,a type of typical fault in rotating machinery,this paper proposes a fault diagnosis method based on the stacked autoencoder(SAE)and ensembled ***,the time-and frequency-domain features of several co-frequency vibration faults are summarized based on the mechanism analysis and calculated using actual vibration *** realize and validate the high-precision diagnosis method of rotating equipment with co-frequency faults proposed in this study,the following three criteria are required:First,to improve the effectiveness and robustness of the ensembled model and the sliding window using data augmentation,adding noise,autoencoder(AE)and SAE methods are analyzed in terms of principle and practical ***,ResNet is used as the feature extractor for the ensembled ResNet-SVM *** extraction is carried out twice,and the extracted co-frequency fault features are more ***,the data augmentation method and ensemble ResNet-SVM are combined for fault diagnosis and compared with other *** experimental results show that the accuracy of the proposed method can exceed 99.9%.

关键词： Co-frequency vribation Data argumentation Ensembeled ResNet-SVM High precision fault diagnosis

Wear behavior of copper material removal during fluid jet polishing:A comparative study between experiment and simulation

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Friction 2024年第8期12卷 1680-1695页

作者： Wenjing ZHANG xin ZHANG Tiancheng AI Dan GUO Guoshun pan State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China Guangdong Provincial Key Laboratory of Optomechatronics Shenzhen 518057China

As a crucial part in micro-electromechanical manufacture,local ultra-precision processing of highly ductile copper is expected to be realized by fluid jet polishing(FJP),which widely utilized in optical *** copper exhibits different wear behavior from stiff and brittle material,there is currently no abrasive wear prediction model applicable for copper to investigate the polishing *** research reveals that the copper material removal is dominated by deformation wear rather than cutting wear through abrasive jet impact experiments and localized wear scars analysis.A three-dimensional gas-liquid-particle triphasic wear model for copper in FJP is developed by considering impact energy and wear mechanism ***,validation assessments at various working pressures and impingement angles achieve the goodness-of-fit up to 0.92–0.97 in quantitative comparison between simulations and experimental measurements,which demonstrate the wear prediction ability of the proposed *** investigation facilitates a better understanding of copper wear mechanism and provides theoretical guidance for FJP process optimization.

关键词： fluid jet polishing(FJP) wear mechanism computational fluid mechanics wear model material removal

Aerodynamic/control integrated optimization method for unpowered high-speed vehicle configuration design

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Chinese Journal of Aeronautics 2024年第7期37卷 153-167页

作者： xin.pan Linlin WANG Li LI Lulu JIANG Gang CHEN State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China Shannxi Key Laboratory for Environment and Control of Flight Vehicle School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China Beijing Institute of Space Long March Vehicle Beijing 100076China AVIC Xi’an Aeronautics Computing Technique Research Institute Xi’an 710068China

The unpowered high-speed vehicle experiences a significant coupling between the disciplines of aerodynamics and control due to its characteristics of high flight speed and extensive maneuverability within large *** conventional aircraft conceptual design process follows a sequential design approach,and there is an artificial separation between the disciplines of aerodynamics and control,neglecting the coupling effects arising from their *** a result,this design process often requires extensive iterations over long periods when applied to high-speed vehicles,and may not be able to effectively achieve the desired design *** enhance the overall performance and design efficiency of high-speed vehicles,this study integrates the concept of Active Control Technology(ACT)from modern aircraft into the philosophy of aerodynamic/control integrated *** integrated optimization strategies,with differences in coupling granularity,have been ***,these strategies are put into action on a biconical vehicle that operates at Mach *** results reveal that the comprehensive performance of the synthesis optimal model derived from the aerodynamic/control integrated optimization strategy is improved by 31.76%and 28.29%respectively compared to the base model under high-speed conditions,demonstrating the feasibility and effectiveness of the method and optimization strategies ***,in comparison to the single-stage strategy,the multi-stage strategy takes into deeper consideration the impact of control *** a result,the control performance of the synthesis opti-mal model derived from the multi-stage strategy improves by 13.99%,whereas the single-stage strategy only achieves a 5.79%*** method enables a fruitful interaction between aerodynamic configuration design and control system design,leading to enhanced overall performance and design ***,it improves the controllability of high-sp

关键词： Aerodynamic/Control Integrated Optimization MDO High-speed vehicle Shape Optimization Controllability

Limits of Uneven Battery Power in Modular Multilevel Converter-based Battery Energy Storage Systems

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 686-695页

作者： Yao pan Xiaofeng Sun Wei Zhao xin Li Yao Cai Institute of Electrical Engineering Yanshan UniversityQinhuangdao 066004China

For modular multilevel converter-based battery energy storage systems (MMC-BESS), uneven power among batteries of SMs will be deduced by battery aging, battery fault, etc., which will degrade performance and even lead to system failure. For maintaining the balance of capacitor voltage, this paper analyzes the limits of the uneven power of batteries, which are presented as the current limits in this paper. According to analysis, an analytical method is proposed that only the dc and fundamental frequency components of the arm current are used to calculate current limits. With the current limits it is able to evaluate the reasonability of power distribution among batteries. Meanwhile, increase of fundamental frequency component will enhance the current limits, and the dc component determines the size relationship between the absolute values of the upper and lower current limits. Finally, simulation model and experiment prototype are built for verifying the theoretical analysis and current limits calculation method, and satisfactory results are provided.

关键词： Arm current balance of capacitor voltage current limits MMC-BESS uneven power

Electric tuning of plasmonic resonances in ultrathin gold nanoribbon arrays

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Photonics Research 2024年第8期12卷 1750-1759页

作者： ZHENxin WANG ALEXEY VKRASAVIN CHENxinYU pan JUNSHENG ZHENG ZHIYONG LI xin GUO ANATOLY VZAYATS LIMIN TONG pan WANG State Key Laboratory of Extreme Photonics and Instrumentation College of Optical Science and EngineeringZhejiang UniversityHangzhou 310027China Department of Physics and London Centre for Nanotechnology King’s College LondonStrandLondon WC2R 2LSUK Jiaxing Key Laboratory of Photonic Sensing&Intelligent Imaging Intelligent Optics&Photonics Research CenterJiaxing Research Institute Zhejiang UniversityJiaxing 314000China

Ultrathin plasmonic nanostructures offer an unparalleled opportunity for the study of light–matter interactions at the nanoscale and realization of compact nanophotonic *** this study,we introduce an ultrathin gold nanoribbon array and demonstrate an electric approach to actively tuning its plasmonic resonance,which leveraging the extreme light confinement capability in the ultrathin plasmonic nanostructure and a robust nanoscale electro-optical effect in indium tin *** the design(to a total thickness as small as 12 nm for a 2-nmthick gold nanoribbon array),we numerically demonstrate a spectral shift in the plasmonic resonance up to 36 nm along with an approximately 16%change in the transmission at a gate voltage below 1.7 V at the wavelength of1.47μ*** work presents progress towards electric tuning of plasmonic resonances in ultrathin metallic nanostructures for various applications including surface-enhanced spectroscopy,spontaneous emission enhancement,and optical modulation.

关键词： plasmon tuning realization

Aggressive fibromatosis of the sigmoid colon:A case report

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3716-3722页

作者： pan-pan Yu xin-Chun Liu Lu Yin Guang Yin Department of Gastrointestinal and Anal Surgery The Affiliated Hangzhou First People's HospitalSchool of MedicineWestlake UniversityHangzhou 310006Zhejiang ProvinceChina Department of Gastric Surgery Zhejiang Cancer HospitalHangzhou 310022Zhejiang ProvinceChina Department of Pathology The Affiliated Hangzhou First People's HospitalSchool of MedicineWestlake UniversityHangzhou 310006Zhejiang ProvinceChina

BACKGROUND Aggressive fibromatosis(AF),also known as desmoid tumor or desmoid-type fibromatosis,is a rare soft tissue neoplasm that can occur in almost any part of the *** it is a benign disease,AF is aggressive and infiltrative and has a high recurrence rate after *** sites for intra-abdominal AF are the small bowel mesentery,retroperitoneum,and *** in the colon is extremely *** SUMMARY Here,we report the first case of sigmoid colon AF,which was accidentally discovered in a 27-year-old woman during laparoscopic *** tomography confirmed a slightly enhanced mass in the sigmoid *** colonoscopy did not reveal a mass in the colonic lumen,but a suspected external compress was found in the sigmoid *** disease involving a gastrointestinal stromal tumor was *** patient underwent laparoscopic exploration,and sigmoidectomy with a negative margin was performed to excise the *** immunohistochemistry revealed that the mass was an *** patient recovered well and was recurrence-free at the 30-month follow-up without adjuvant *** AF should be considered in the differential diagnosis of subepithelial colon *** resection alone can achieve good outcomes.

关键词： Aggressive fibromatosis Desmoid tumor Sigmoid mass Subepithelial tumor Case report

Rock physical characteristics of deep dolomite under complex geological conditions: A case study of 4th Member of Sinian Dengying Formation in the Sichuan Basin, China

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Petroleum Science 2024年第4期21卷 2370-2382页

作者： Chuang Li Shu-xin.pan Hong-Bin Wang Ji-xin Deng Jian-Guo Zhao Zhi Li Yu Zhang Northwest Branch of Research Institute of Petroleum Exploration & Development Department of Geophysics and Exploration College of Geophysics Chengdu University of Technology State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing)

The deep-ultra deep carbonate reservoir in China, commonly subjected to modification of multi-stage diagenesis, has extremely high heterogeneity. Conventional rock physics analysis cannot accurately identify the elastic responses of reservoir. Here, the rock physics properties of the dolomite from the 4th Member of the Sinian Dengying Formation are experimentally measured, and the change law of rock physics characteristics is investigated within the framework of the diagenetic processes by the analysis of the elastic and petrologic characteristics, pore structure, and sedimentary environments. The results show that the differentiated diagenesis results in different pore structure characteristics and microtexture characteristics of the rock. The microbial dolomite of the algal mound-grain beach facies is subjected to the contemporaneous microbial dolomitization and seepage-reflux dolomitization, penecontemporaneous selective dissolution, burial dolomitization, and hydrothermal dolomitization. The resultant crystalline dolomite is found with one main type of the dolomite crystal contact boundaries,and the dissolution pore is extensive development. The siliceous, muddy, and limy dolomite of the interbeach sea environment mainly experiences the weak capillary concentration dolomitization, intensive mechanical compaction-induced densification, and burial dolomitization. Such crystalline dolomite is observed with four types of contact boundaries, namely the dolomite contact, clay contact, quartz contact, and calcite contact boundaries, and porosity mostly attributed to residual primary inter-granular or crystalline pores. The samples with the same crystal boundary condition have consistent correlations between the compressional-and shear-wave velocities, and between the compressional-wave velocity and the velocity ratio. Additionally, the variation of the acoustic velocity with effective pressure and the intensity of pore-scale fluid-related dispersion are controlled by t

关键词： Deep-ultra deep carbonate reservoirs Rock physics properties Dolomite Seismic elastic properties Micro-crack Pore structure types

Simulation study of the performance of the Very Large Area gamma-ray Space Telescope

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Nuclear Science and Techniques 2024年第9期35卷 1-17页

作者： Xu pan Wei Jiang Chuan Yue Shi-Jun Lei Yu-xin Cui Qiang Yuan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China

The Very Large Area gamma-ray Space Telescope(VLAST)is a mission concept proposed to detect gamma-ray photons through both Compton scattering and electron–positron pair production mechanisms,thus enabling the detection of photons with energies ranging from MeV to *** project aims to conduct a comprehensive survey of the gamma-ray sky from a low-Earth orbit using an anti-coincidence detector,a tracker detector that also serves as a low-energy calorimeter,and a high-energy imaging *** developed a Monte Carlo simulation application of the detector using the GEANT4 toolkit to evaluate the instrument performance,including the effective area,angular resolution,and energy resolution,and explored specific optimizations of the detector *** simulation-based analysis indicates that the current design of the VLAST is physically feasible,with an acceptance above 10 m^(2)sr which is four times larger than that of the Fermi-LAT,an energy resolution better than 2%at 10 GeV,and an angular resolution better than 0.2◦at 10 *** VLAST project promises to make significant contributions to the field of gamma-ray astronomy and enhance our understanding of the cosmos.

关键词： Space astronomy Gamma-ray telescope Calorimeter Monte Carlo simulation