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Prediction of undeformed chip thickness distribution and surface roughness in ultrasonic vibration grinding of inner hole of bearings

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第4期25卷 311-323页

作者： Yanqin LI Daohui XIANG Guofu GAO feng jiao Bo ZHAO School of Mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo 454000China

Ultrasonic vibration grinding differs from traditional grinding in terms of its material removal *** randomness of grain-workpiece interaction in ultrasonic vibration grinding can produce variable chips and impact the surface roughness of ***,previous studies used iterative method to calculate the unformed chip thickness(UCT),which has low computational *** this study,a symbolic difference method is proposed to calculate the *** UCT distributions are obtained to describe the stochastic interaction characteristics of ultrasonic grinding ***,the UCT distribution characteristics under different machining parameters are ***,a surface roughness prediction model is established based on the UCT ***,the correctness of the model is verified by *** study provides a quick and accurate method for predicting surface roughness in longitudinal ultrasonic vibration grinding.

关键词： Ultrasonic vibration grinding Undeformed chip thickness(UCT) Distribution characteristics Surface roughness

Visible Light Indoor Positioning System Based on Pisarenko Harmonic Decomposition and Neural Network

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Chinese Journal of Electronics 2024年第1期33卷 195-203页

作者： Li ZHAO Yi REN Qi WANG Lange deng feng ZHANG School of Electronic Information Engineering Xi’an Technological University

Visible-light indoor positioning is a new generation of positioning technology that can be integrated into smart lighting and optical communications. The current received signal strength(RSS)-based visible-light positioning systems struggle to overcome the interferences of background and indoor-reflected noise. Meanwhile, when ensuring the lighting, it is impossible to use the superposition of each light source to accurately distinguish light source information; furthermore, it is difficult to achieve accurate positioning in complex indoor environments. This study proposes an indoor positioning method based on a combination of power spectral density detection and a neural network. The system integrates the mechanism for visible-light radiation detection with RSS theory, to build a back propagation neural network model fitting for multiple reflection channels. Different frequency signals are loaded to different light sources at the beacon end, and the characteristic frequency and power vectors are obtained at the location end using the Pisarenko harmonic decomposition method. Then, a complete fingerprint database is established to train the neural network model and conduct location tests. Finally, the location effectiveness of the proposed algorithm is verified via actual positioning experiments. The simulation results show that, when four groups of sinusoidal waves with different frequencies are superimposed with white noise, the maximum frequency error is 0.104 Hz and the maximum power error is 0.0362 W. For the measured positioning stage, a 0.8 m × 0.8 m × 0.8 m solid wood stereoscopic positioning model is constructed, and the average error is 4.28 cm. This study provides an effective method for separating multi-source signal energies, overcoming background noise, and improving indoor visible-light positioning accuracies.

关键词： Neural networks Measurement uncertainty Position measurement Harmonic analysis Light emitting diodes Frequency estimation Indoor positioning systems

Multi-scale hash encoding based neural geometry representation

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Computational Visual Media 2024年第3期10卷 453-470页

作者： Zhi deng Haoyao Xiao Yining Lang Hao feng Juyong Zhang School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026China Alibaba Artiﬁcial Intelligence Governance Laboratory Alibaba GroupHangzhou 310017China

Recently, neural implicit function-basedrepresentation has attracted more and more attention,and has been widely used to represent surfacesusing differentiable neural networks. However, surfacereconstruction from point clouds or multi-view imagesusing existing neural geometry representations stillsuffer from slow computation and poor accuracy. Toalleviate these issues, we propose a multi-scale hashencoding-based neural geometry representation whicheffectively and efficiently represents the surface asa signed distance ﬁeld. Our novel neural networkstructure carefully combines low-frequency Fourierposition encoding with multi-scale hash encoding. Theinitialization of the geometry network and geometryfeatures of the rendering module are accordinglyredesigned. Our experiments demonstrate that theproposed representation is at least 10 times faster forreconstructing point clouds with millions of *** also signiﬁcantly improves speed and accuracyof multi-view reconstruction. Our code and modelsare available at https://***/dengzhi-USTC/Neural-Geometry-Reconstruction.

关键词： neural geometry representation hash encoding point cloud reconstruction multi-view reconstruction

Buckling Properties of Water-Drop-Shaped Pressure Hulls with Various Shape Indices Under Hydrostatic External Pressure

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China Ocean Engineering 2024年第1期38卷 1-17页

作者： DING Xiao-de ZHANG Jian WANG Fang jiao Hui-feng WANG Ming-lu School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Shanghai Engineering Research Center of Marine Renewable Energy College of Engineering Science and Technol-ogyShanghai Ocean UniversityShanghai 201306China China Ship Scientific Research Center Wuxi 214082China

The water-drop-shaped pressure hull has a good streamline,which has good application prospect in the underwater ***,this study conducted analytical,experimental and numerical investigation of the buckling properties of water-drop-shaped pressure hulls under hydrostatic pressure.A water-drop experiment was conducted to design water-drop-shaped pressure hulls with various shape *** critical loads for the water-drop-shaped pressure hulls were resolved by using Mushtari’s *** numerical simulations including linear buckling analysis and nonlinear buckling analysis including eigenmode imperfections were *** results indicated that the critical loads resolved by Mushtari's formula were in good agreement with the linear buckling loads from the numerical *** formula can be extended to estimate the buckling capacity of water-drop-shaped pressure *** addition,three groups of pressure hulls were fabricated by using stereolithography,a rapid prototyping ***,three groups of the pressure hulls were subjected to ultrasonic measurements,optical scanning,hydrostatic testing and numerical *** experimental results were consistent with the numerical *** results indicate that the sharp end of the water-drop-shaped pressure hulls exhibited instability compared with the blunt *** paper provides a new solution to the limitations of experimental studies on the water-drop-shaped pressure hulls as well as a new configuration and evaluation method for underwater observatories.

关键词： buckling pressure hull water drop underwater observatory

Effect of electrolyte cation-mediated mechanism on electrocatalytic carbon dioxide reduction

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Chinese Chemical Letters 2024年第7期35卷 139-146页

作者： Yuan Dong Mutian Ma Zhenyang jiao Sheng Han Likun Xiong Zhao deng Yang Peng Soochow Institute of Energy and Material Innovations College of EnergyJiangsu Key Laboratory of Advanced Carbon Materials and Wearable Energy TechnologiesSoochow UniversitySoochow 215006China Jiangsu Key Laboratory of Advanced Negative Carbon Technologies Soochow UniversitySoochow 215123China School of Chemistry and Chemical Engineering Shihezi UniversityShihezi 832003China School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai 201418China

The steep reduction in costs and systematic optimization of renewable electricity has ignited an intensifying interest in harnessing electroreduction of carbon dioxide(CO_(2)RR)for the generation of chemicals and *** focus of research over the past few decades has been on the optimization of the electrode and the electrolyte ***,cation species in the latter have recently been found to dramatically alter the selectivity of CO_(2)RR and even their catalytic activity by multiple orders of *** a result,the selection of cations is a critical factor in designing catalytic interfaces with high selectivity and efficiency for targeted *** decision-making regarding cation selection relies on a comprehensive understanding of prevailing electrolyte effect models that have been used to elucidate observed experimental *** this perspective,we review the hypotheses that explain how electrolyte cations influence CO_(2)RR by mechanisms such as through tuning of the interfacial electric field,buffering of the local pH,stabilization of the key intermediates and regulation of the interfacial *** endeavor is to elucidate the molecular mechanisms underpinning cation effects,thus fostering the evolution of more holistic and universally applicable predictive *** this regard,we highlight the current challenges in this area of research,while also identifying potential avenues for future investigations.

关键词： CO_(2)electrocatalytic reduction Cation effects Catalytic mechanisms Catalytic interfaces Electric double layer

Metagenomic insights into microorganisms and antibiotic resistance genes of waste antibiotic fermentation residues along production,storage and treatment processes

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Journal of Environmental Sciences 2024年第2期136卷 45-55页

作者： Ziming Han Xiao Luan Haodi feng Yanqin deng Min Yang Yu Zhang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery Beijing 100085China Wuhan Agricultural Inspection Center Wuhan 430016China University of Chinese Academy of Sciences Beijing 100049China

Antibiotic fermentation residue(AFR)is nutrient-rich solid waste generated from fermentative antibiotic production *** is demonstrated that AFR contains high-concentration of remaining antibiotics,and thus may promote antibiotic resistance development in receiving environment or feeding farmed ***,the dominate microorganisms and antibiotic resistance genes(ARGs)in AFRs have not been adequately explored,hampering understanding on the potential antibiotic resistance risk development caused by ***,seven kinds of representative AFRs along their production,storage,and treatment processes were collected,and multiple methods including amplicon sequencing,metagenomic sequencing,and bioinformatic approaches were adopted to explore the biological characteristics of *** expected,antibiotic fermentation producer was found as the predominant species in raw AFRs,which were collected at the outlet of fermentation ***,except for producer species,more environment-derived species persisted in stored AFRs,which were temporarily stored at a semi-open *** genus,classified as Firmicutes phylum and Bacilli class,became predominant bacterial taxa in stored AFRs,which might attribute to its tolerance to high concentration of *** from metagenomic sequencing together with assembly and binning approaches showed that these newly-colonizing species(e.g.,Lactobacillus genus)tended to carry ARGs conferring resistance to the remaining ***,after thermal treatment,remaining antibiotic could be efficiently removed from AFRs,and microorganisms together with DNA could be strongly *** sum,the main risk from the AFRs was the remaining antibiotic,while environment-derived bacteria which tolerate extreme environment,survived in ARFs with high content antibiotics,and may carry ***,hydrothermal or other harmless treatment technologies are recommended to remove antibiotic content and inactivate bacteria befor

关键词： Pharmaceutical manufacturing Antibiotic mycelia residue Antibiotic resistance bacteria Thermal treatment Solid waste

Thermoelectric Properties of an Indandione-Terminated Quinoidal Compound:Effect of the n-Type Dopants

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Chinese Journal of Chemistry 2024年第9期42卷 997-1003页

作者： Yingying Liu Cheng Wang Tianzuo Wang Fei jiao Shaoqiang Dong Yunfeng deng Yanhou Geng School of Materials Science and Engineering and Tianjin Key Laboratory of Molecular Optoelectronic Science Tianjin Universityand Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin 300072China Institute of Molecular Aggregation Science Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Molecular Optoelectronic Science Department of ChemistrySchoolof ScienceTianjin UniversityTianjin300072China Joint Schoolof NationalUniversity of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New City FuzhouFujian350207China

The investigation of n-type doping holds a significant interest for the application of ***,the doping of an indandione-terminated compound Q-4F with a singlet open-shell ground state was studied using two n-dopants N-DMBI and *** of these two dopants can effectively dope Q-4F due to the large offset between the singly occupied molecular orbital(SOMO)of dopants and the lowest unoccupied molecular orbital(LUMO)of Q-4F.N-DMBI has a higher doping ability than LCV as demonstrated by the UV-vis-NIR and EPR ***,in comparison to N-DMBI doped Q-4F,LCV doped system exhibits much higher electrical conductivity and power factor due to its unperturbed molecular packing and favorable morphology after *** optimal conductivity of LCV doped Q-4F is 7.16×10^(-2)±0.16 S·cm^(-1) and the highest power factor reaches 12.3±0.85μW·m–1·K^(-2).These results demonstrate that the modulation of n-dopants is a powerful strategy to balance the doping efficiency and microstructure toward a maximum thermoelectric performance.

关键词： n-Doping Indandione Quinoidal compounds Organic thermoelectrics Electron transfer Organic electronics Energy conversion

A Comprehensive Survey on Deep Learning Multi-Modal Fusion:Methods,Technologies and Applications

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Computers, Materials & Continua 2024年第7期80卷 1-35页

作者： Tianzhe jiao Chaopeng Guo Xiaoyue feng Yuming Chen Jie Song Software College Northeastern UniversityShenyang110819China

Multi-modal fusion technology gradually become a fundamental task in many fields,such as autonomous driving,smart healthcare,sentiment analysis,and human-computer *** is rapidly becoming the dominant research due to its powerful perception and judgment *** complex scenes,multi-modal fusion technology utilizes the complementary characteristics of multiple data streams to fuse different data types and achieve more accurate ***,achieving outstanding performance is challenging because of equipment performance limitations,missing information,and data *** paper comprehensively reviews existing methods based onmulti-modal fusion techniques and completes a detailed and in-depth *** to the data fusion stage,multi-modal fusion has four primary methods:early fusion,deep fusion,late fusion,and hybrid *** paper surveys the three majormulti-modal fusion technologies that can significantly enhance the effect of data fusion and further explore the applications of multi-modal fusion technology in various ***,it discusses the challenges and explores potential research ***-modal tasks still need intensive study because of data heterogeneity and *** complementary information and eliminating redundant information between modalities is critical in multi-modal *** data fusion methods may introduce extra noise and lead to worse *** paper provides a comprehensive and detailed summary in response to these challenges.

关键词： Multi-modal fusion representation translation alignment deep learning comparative analysis

Diffusion of nanochannel-confined knot along a tensioned polymer

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Communications in Theoretical Physics 2024年第4期76卷 158-166页

作者： Guobing Cai Yong Li Yuyu feng Zhouhui deng Yanhui Liu College of Physics Guizhou UniversityGuiyang 550025China Kechuang Industrial Development Company Limited Guian New AreaGuiyang 550025China State Key Laboratory of Public Big Data Guizhou UniversityGuiyang 550025China

The knots frequently occur in biopolymer and their diffusion plays an active role in the gene *** this work,Langevin dynamics simulations were carried out to detect the diffusion behaviours of a knot along a tensioned polymer in different spatial *** polymer accommodating a knot was tethered to two macrospheres to block the unravelling of the *** a result,the curves for the diffusion coefficients of the knot with different bending stiffness as a function of the tension in different spatial constraints were *** the space without constraints or with weak constraints,the corresponding curves for the knot with relatively large bending stiffness exhibited two turnover *** the contrary,for the knot with relatively small bending stiffness,the diffusion coefficients were monotonically reduced with increasing ***,in a space with strong constraints,all the curves showed one turnover behaviour regardless of the bending *** turnover behaviours divided the curves into different regimes,and the dominant diffusion mechanisms in the regimes,namely,knot-region breathing,self-reptation,and internal friction,were clearly *** effective friction coefficientsξof the knots with 3_(1),4_(1),5_(1) and 5_(2) types as a function of the knot size N at a fixed tension were well fitted by the relationξ∝*** effective friction coefficients of the knots at relatively large tension f>3 sharply increased with the knot complexity,which is not dependent on the spatial *** contrast,the values of these coefficients at relatively small tension f≤3 were remarkably dependent on the spatial *** work not only provides valuable simulation results to assist the understanding of the diffusion of DNA knot,but also highlights the single-molecule design for the manipulation of DNA knots in future.

关键词： knot langevin dynamics simulations diffusion coefficient self-reptation knot-region breathing internal friction