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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 *** 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 *** have studied how to measure,detect,model,identify,reduce,and compensate the geometric *** 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 *** 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 ***,volumetric geometric error modeling,tracing,and compensation techniques for five-axis machine tools are emphatically ***,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

Sliding behaviors of the trapezoidal roof rock block under a lateral dynamic disturbance

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Journal of Rock Mechanics and geotechnical Engineering 2024年第3期16卷 741-760页

作者： feng dai Wancheng Zhu Min Ren Shunchuan Wu Leilei Niu Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming650093China Center for Rock Instability and Seismicity Research Department of Mining EngineeringSchool of Resource and Civil EngineeringNortheastern UniversityShenyang110819China

The surrounding rock of underground space is always affected by external dynamic disturbance from the side position,such as blasting vibration from a stope at the same level or seismic waves from adjacent strata.A series of laboratory tests,numerical simulations and theoretical analyses were carried out in this study to disclose the sliding mechanism of roof rock blocks under lateral ***,the experiments on trapezoidal key block under various clamping loads and disturbance were conducted,followed by numerical simulations using the fast Lagrangian analysis of continua(FLAC3d).Then,based on the conventional wave propagation model and the classical shear-slip constitutive model,a theoretical model was proposed to capture the relative displacement between blocks and the sliding displacement of the key *** results indicate that the sliding displacement of the key block increased linearly with the disturbance energy and decreased exponentially with the clamping load when the key block was disturbed to slide(without instability).Meanwhile,when the key block was disturbed to fall,two types of instability process may appear as immediate type or delayed *** addition,the propagation of stress waves in the block system exhibited obvious low-velocity and lowfrequency characteristics,resulting in the friction reduction effect appearing at the contact interface,which is the essential reason for the sliding of rock *** results can be applied to practical underground engineering and provide valuable guidance for the early detection and prevention of rockfalling disasters.

关键词： Lateral dynamic disturbance Trapezoidal rock block system Low-velocity and low-frequency wave Friction reduction effect Instability mode

Ferric ion-triggered surface oxidation of galena for efficient chalcopyrite-galena separation

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 261-267页

作者： Qiancheng Zhang Limin Zhang feng Jiang Honghu Tang Li Wang Wei Sun School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Changsha 410083China School of Resource and Environment Hunan University of Technology and BusinessChangsha 410083China

The efficient separation of chalcopyrite(CuFeS2)and galena(PbS)is essential for optimal resource ***,find-ing a selective depressant that is environmentally friendly and cost effective remains a *** various techniques,such as mi-croflotation tests,Fourier transform infrared spectroscopy,scanning electron microscopy(SEM)observation,X-ray photoelectron spec-troscopy(XPS),and Raman spectroscopy measurements,this study explored the use of ferric ions(Fe^(3+))as a selective depressant for *** results of flotation tests revealed the impressive selective inhibition capabilities of Fe^(3+)when used *** analysis showed that Fe^(3+)significantly reduced the adsorption of isopropyl ethyl thionocarbamate(IPETC)on the galena surface while having a minimal impact on *** analysis using SEM,XPS,and Raman spectra revealed that Fe^(3+)can oxidize lead sulfide to form compact lead sulfate nanoparticles on the galena surface,effectively depressing IPETC adsorption and increasing surface *** findings provide a promising solution for the efficient and environmentally responsible separation of chalcopyrite and galena.

关键词： galena chalcopyrite ferric ions flotation separation surface oxidation

Automatic Miscalibration detection and Correction of LidAR and Camera Using Motion Cues

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 318-329页

作者： Pai Peng dawei Pi guodong Yin Yan Wang Liwei Xu Jiwei feng School of Mechanical Engineering Southeast UniversityNanjing 211102China School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210014China School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingaporeSingapore

This paper aims to develop an automatic miscalibration detection and correction framework to maintain accurate calibration of LidAR and camera for autonomous vehicle after the sensor ***,a monitoring algorithm that can continuously detect the miscalibration in each frame is designed,leveraging the rotational motion each individual sensor ***,as sensor drift occurs,the projection constraints between visual feature points and LidAR 3-d points are used to compute the scaled camera motion,which is further utilized to align the drifted LidAR scan with the camera ***,the proposed method is sufficiently compared with two representative approaches in the online experiments with varying levels of random drift,then the method is further extended to the offline calibration experiment and is demonstrated by a comparison with two existing benchmark methods.

关键词： Autonomous vehicle LidAR and camera Miscalibration detection and correction Sensor drift

Mechanism of internal thermal runaway propagation in blade batteries

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Journal of Energy Chemistry 2024年第2期89卷 184-194,I0005页

作者： Xuning feng Fangshu Zhang Wensheng Huang Yong Peng Chengshan Xu Minggao Ouyang School of Vehicle and Mobility Tsinghua UniversityBeijing 100084China

Blade batteries are extensively used in electric vehicles,but unavoidable thermal runaway is an inherent threat to their safe *** study experimentally investigated the mechanism underlying thermal runaway propagation within a blade battery by using a nail to trigger thermal runaway and thermocouples to track its propagation inside a *** results showed that the internal thermal runaway could propagate for up to 272 s,which is comparable to that of a traditional battery *** velocity of the thermal runaway propagation fluctuated between 1 and 8 mm s^(-1),depending on both the electrolyte content and high-temperature gas *** the early stages of thermal runaway,the electrolyte participated in the reaction,which intensified the thermal runaway and accelerated its *** the battery temperature increased,the electrolyte evaporated,which attenuated the acceleration *** diffusion affected thermal runaway propagation through both heat transfer and mass *** experimental results indicated that gas diffusion accelerated the velocity of thermal runaway propagation by 36.84%.We used a 1d mathematical model and confirmed that convective heat transfer induced by gas diffusion increased the velocity of thermal runaway propagation by 5.46%-17.06%.Finally,the temperature rate curve was analyzed,and a three-stage mechanism for internal thermal runaway propagation was *** Stage I,convective heat transfer from electrolyte evaporation locally increased the temperature to 100℃.In Stage II,solid heat transfer locally increases the temperature to trigger thermal *** StageⅢ,thermal runaway sharply increases the local *** proposed mechanism sheds light on the internal thermal runaway propagation of blade batteries and offers valuable insights into safety considerations for future design.

关键词： Lithium-ion battery Blade battery Thermal runaway Internal thermal runaway propagation

Tailoring NH4+ storage by regulating oxygen defect in ammonium vanadate

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green Energy & Environment 2024年第7期9卷 1171-1182页

作者： Yanyan Liu Ziyi feng Hanmei Jiang Xueying dong Changgong Meng Yifu Zhang State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology College of Environmental and Chemical Engineering Dalian University

defect engineering is an effective strategy for modifying the energy storage materials to improve their electrochemical ***, the impact of oxygen defect and its content on the electrochemical performances in the burgeoning aqueous NH+4storage field remains explored. Therefore, for the first time in this work, an oxygen-defective ammonium vanadate [（NH4）2V10O25·8H2O, denoted as Od-NHVO] with a novel 3d porous flower-like architecture was achieved via the reduction of thiourea in a mild reaction condition, which is a facile method that can realize the intention to regulate the oxygen defect content, with the capability of mass-production. The as-prepared OdM-NHVO with moderate oxygen defect content can deliver a stable specific capacitance output(505 F g-1, 252 mAh g-1at 0.5 A g-1with ～80% capacitance retention after 10,000 cycles), which benefits from extra active sites, unimpeded NH+4-migration path and relatively high structure integrity. In contrast, low oxygen defect content will lead to the torpid electrochemical reaction kinetics while too high content of it will reduce the chargestorage capability and induce structural disintegration. The superior NH+4-storage behavior is achieved with the reversible intercalation/deintercalation process of NH+4accompanied by forming/breaking of hydrogen bond. As expected, the assembled flexible OdM-NHVO//PTCdI quasi-solid-state hybrid supercapacitor（FQSS HSC） also exhibits high areal capacitance, energy density and reliable flexibility. This work provides a new avenue for developing materials with oxygen-deficient structure for application in various aqueous non-metal cation storage systems.

关键词： Ammonium vanadate Oxygen defect Ammonium-ion storage Hybrid supercapacitors Electrochemical performance

Evolution of In783 alloy in microstructure and properties enduring different service times

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Rare Metals 2024年第1期43卷 334-341页

作者： Zhong-Shuai Han Jin-feng du Jun Liang Zheng Zhang School of Material Science and Engineering Beihang UniversityBeijing 100191China Shenhua guohua(Beijing)Electric Power Research Institute Co. Ltd.Beijing 100025China

Impact, tensile, and fatigue tests were performed in In783 alloy serving 4000, 23,000 and 48,000 h. The microstructure was then analysed by optical microscopy(OM), scanning electron microscopy(SEM), and transmission electron microscopy(TEM) to probe the relationship between microstructure and properties. The results show that a new Ni_(5)Al_(3) phase is found, which grows gradually in β phase with serving time increasing,destroying the martensitic structure of the β phase, and degenerating the toughness of the β phase(approximately13.88% reduction). Therefore, the degradation of the βphase results in a sharp dropping of the resistance to stress accelerated grain boundary oxygen(SAgBO) during serving;thus, the intergranular fracture morphology degree increases with duration of service(almost 40% increase from the fractured surface). In addition, the strength of alloy will be gradually enhanced when the γ'phase becomes relatively bulky with serving time increasing due to considerable distortion of the dislocations as a result of the spacing of individual particles, in which any movement of the dislocation will have to overcome a larger number of obstacles per unit length.

关键词： In783 Microstructure Properties βphase Ni_(5)Al_(3)phase

Color-polarization synergistic target detection method considering shadow interference

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defence Technology（防务技术） 2024年第7期37卷 50-61页

作者： Bin feng Jinpei Xiao Junchao Zhang Lin Li Yunlong Wu Qing Ye School of Automation Northwestern Polytechnical UniversityXi'an710072China School of Automation Central South UniversityChangsha410083China State Key Laboratory of Pulsed Power Laser Technology National University of Defense TechnologyHefei230037China

Aiming at the problem of shadow interference in UAV's ground reconnaissance,a color and polarization synergistic target detection method is proposed for anti-shadow interference,based on the influence of two physical characteristics(wavelength and polarization)under different illuminations.A valid fusion strategy is proposed via integrating two separate detection results on color and polarization ***,a local enhancement and recognition module(LER)is introduced to boost the *** on our built dataset,experimental results show that our method achieves mAPof 87.76%,and12.37%higher than that of color image and 14.68%higher than that of polarization image.

关键词： Electro-optical countermeasure ground reconnaissance Color-polarization Shadow interference Target recognition

The Adjustment Analysis Method of the Active Surface Antenna Based on Convolutional Neural Network

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Research in Astronomy and Astrophysics 2024年第6期24卷 294-306页

作者： You Ban Shang Shi Na Wang Qian Xu Shufei feng School of Mechanical Engineering Xinjiang UniversityUrumqi 830017China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China School of Mechanical Engineering Dongguan University of TechnologyDongguan 523808China

Active surface technique is one of the key technologies to ensure the reflector accuracy of the millimeter/submillimeter wave large reflector *** antenna is complex,large-scale,and high-precision equipment,and its active surfaces are affected by various factors that are difficult to comprehensively deal *** this paper,based on the advantage of the deep learning method that can be improved through data learning,we propose the active adjustment value analysis method of large reflector antenna based on deep *** method constructs a neural network model for antenna active adjustment analysis in view of the fact that a large reflector antenna consists of multiple panels spliced *** on the constraint that a single actuator has to support multiple panels(usually 4),an autonomously learned neural network emphasis layer module is designed to enhance the adaptability of the active adjustment neural network *** classical 8-meter antenna is used as a case study,the actuators have a mean adjustment error of 0.00252 mm,and the corresponding antenna surface error is0.00523 *** active adjustment result shows the effectiveness of the method in this paper.

关键词： techniques:radar astronomy telescopes methods:analytical methods:numerical