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A Deep Generative Model with Multiscale Features Enabled Industrial Internet of Things for Intelligent Fault Diagnosis of Bearings

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Research 2023年第3期6卷 57-68页

作者： He-xuan Hu yicheng Cai Qiang Hu Ye zhang Key Laboratory of Water Big Data Technology of Ministry of Water Resources Hohai UniversityNanjing 211100P.R.China College of Computer and Information Hohai UniversityNanjing 211100P.R.China

Effective condition monitoring and fault diagnosis of bearings can not only maximize the life of rolling bearings and prevent unexpected shutdowns caused by equipment failures but also eliminate unnecessary costs and waste caused by excessive maintenance.However,the existing deep-learning-based bearing fault diagnosis models have the following defects.First of all,these models have a large demand for fault data.Second,the previous models only consider that single-scale features are generally less effective in diagnosing bearing faults.Therefore,we designed a bearing fault data collection platform based on the Industrial Internet of Things,which is used to collect bearing status data from sensors in real time and feed it back into the diagnostic model.On the basis of this platform,we propose a bearing fault diagnosis model based on deep generative models with multiscale features(DGMMFs)to solve the above problems.The DGMMF model is a multiclassification model,which can directly output the abnormal type of the bearing.Specifically,the DGMMF model uses 4 different variational autoencoder models to augment the bearing data and integrates features of different scales.Compared with single-scale features,these multiscale features contain more information and can perform better.Finally,we conducted a large number of related experiments on the real bearing fault datasets and verified the effectiveness of the DGMMF model using multiple evaluation metrics.The DGMMF model has achieved the highest value under all metrics,among which the value of precision is 0.926,the value of recall is 0.924,the value of accuracy is 0.926,and the value of F1 score is 0.925.

关键词： fault bearings diagnosis

A Direct Route to Tetrahydropyridazine Derivatives via DMAP-Catalyzed [4+2] Annulation of Allenoates with Arylazosulfones

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Chinese Journal of Chemistry 2023年第22期41卷 3031-3036,I0002页

作者： Xin Ji Ziyang Li Jinfeng zhang yicheng zhang Ling-Guo Meng Key Laboratory of Green and Precise Synthetic Chemistry and Applications Ministry of EducationSchool of Chemistry and Materials ScienceHuaibei Normal UniversityHuaibeiAnhui 235000China

Herein,a DMAP-catalyzed[4+2]annulation ofα-substituted allenoates with arylazosulfones is reported,which affords facile access to tetrahydropyridazine derivative in synthetically useful yields.This reaction features mild conditions and good functional group tolerance.Moreover,the resultant products can be readily transformed into pyridazin-3-one derivatives in the presence of DDQ.

关键词： DMAP [4+2]Cycloaddition Tetrahydropyridazihe derivatives Pyridazin-3-one derivatives Allenes Zwitterions N-Heterocycles

A pre-strain strategy of current collectors for suppressing electrode debonding in lithium-ion batteries

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Applied Mathematics and Mechanics(English Edition) 2023年第4期44卷 547-560页

作者： Bo RUI Bo LU yicheng SONG Junqian zhang Department of Mechanics Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai UniversityShanghai 200444China Shanghai Frontier Science Center of Mechanoinformatics Shanghai UniversityShanghai 200444China Zhejiang Laboratory Hangzhou 311100China

The interfacial debonding between the active layer and the current collector has been recognized as a critical mechanism for battery fading,and thus has attracted great efforts focused on the related analyses.However,much still remains to be studied regarding practical methods for suppressing electrode debonding,especially from the perspective of mechanics.In this paper,a pre-strain strategy of current collectors to alleviate electrode debonding is proposed.An analytical model for a symmetric electrode with a deformable and limited-thickness current collector is developed to analyze the debonding behavior involving both a pre-strain of the current collector and an eigen-strain of the active layers.The results reveal that the well-designed pre-strain can significantly delay the debonding onset(by up to 100%)and considerably reduce the debonding size.The critical values of the pre-strain are identified,and the pre-strain design principles are also provided.Based on these findings,this work sheds light on the mechanical design to suppress electrode degradation.

关键词： pre-strain current collector electrode debonding lithium-ion battery(LIB) mechanically-based design

Evaluating the performance and influencing factors of three portable black carbon monitors for field measurement

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Journal of Environmental Sciences 2024年第5期139卷 320-333页

作者： Liqing Wu yicheng Shen Fei Che Yuzhe zhang Jian Gao Chong Wang State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Jinan Ecological Environmental Protection Grid-Based Supervision Center Jinan 250013China

Black carbon(BC)is associated with adverse human health and climate change.Mapping BC spatial distribution imperatively requires low-cost and portable devices.Several portable BC monitors are commercially available,but their accuracy and reliability are not always satisfactory during continuous field observation.This study evaluated three models of portable black carbon monitors,C12,MA350 and DST,and investigates the factors that affect their performance.The monitors were tested in urban Beijing,where portable devices running for one month alongside a regular-size reference aethalometer AE33.The study considers several factors that could influence the monitors'performance,including ambient weather,aerosol composition,loading artifacts,and built-in algorithms.The results show that MA350and DST present considerable discrepancies to the reference instrument,mainly occurring at lower concentrations(0-500 ng/m^(3))and higher concentrations(2500-8000 ng/m^(3)),respectively.These discrepancies were likely caused by the anomalous noise of MA350 and the loading artifacts of DST.The study also suggests that the ambient environment has limited influence on the monitors'performance,but loading artifacts and accompanying compensation algorithms can result in unrealistic data.Based on the evaluation,the study suggests that C12 is the best choice for unsupervised field measurement,DST should be used in scenarios where frequent maintenance is available,and MA350 is suitable for research purposes with post-processing applicable.The study highlights the importance of assigning portable BC monitors to appropriate applications and the need for optimized real-time compensation algorithms.

关键词： Black carbon Aethalometer Loading artifact Performance evaluation Portable device

Understanding Modulus Variation of the Active Layers of Silicon Composite Electrodes

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Acta Mechanica Solida Sinica 2022年第6期35卷 987-995页

作者： Bowen Sun Yanfei Zhao yicheng Song Junqian zhang Bo Lu Department of Mechanics Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai200444China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai UniversityShanghai200444China Department of Civil Engineering School of Mechanics and Engineering ScienceShanghai UniversityShanghai200444China Zhejiang Laboratory Hangzhou311100China

The variation of the effective modulus of silicon composite electrodes,which is a fundamental feature to analyze the coupled mechanical–electrochemical behavior of Si-based electrodes in high-capacity lithium-ion batteries,remains qualitatively controversial.To clarify the contradictory experimental results,numerical modeling of a representative volume element with silicon particles,carbon-binder domains(CBDs),and pores has been performed for the lithiation process.The key parameters for modulus variation were identified and evaluated.A mesostructure change is proposed to be a crucial mechanism that affects the modulus variation,and silicon softening is another key mechanism.Silicon softening and the decreasing CBD volume fraction collectively result in a decrease in the effective modulus of the composite,whereas an increase in the silicon volume fraction along with a decrease in porosity has the opposite effect.The findings of this work provide an in-depth and fundamental understanding of the mechanical properties of silicon composite electrodes.

关键词： Modulus variation Silicon composite electrode Active layer Mesostructure change Silicon softening

Imaging algorithm of multi-ship motion target based on compressed sensing

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Journal of Systems Engineering and Electronics 2016年第4期27卷 790-796页

作者： Lin zhang yicheng Jiang School of Electronics and Information Engineering Harbin Institute of Technology

An imaging algorithm based on compressed sensing（CS） for the multi-ship motion target is presented. In order to reduce the quantity of data transmission in searching the ships on a large sea area, both range and azimuth of the moving ship targets are converted into sparse representation under certain signal basis. The signal reconstruction algorithm based on CS at a distant calculation station, and the Keystone and fractional Fourier transform（FRFT） algorithm are used to compensate range migration and obtain Doppler frequency. When the sea ships satisfy the sparsity, the algorithm can obtain higher resolution in both range and azimuth than the conventional imaging algorithm. Some simulations are performed to verify the reliability and stability.

关键词： synthetic aperture radar（SAR） compressed sensing（CS） multiple ships moving target sparse reconstruction

Advances in Atomic Layer Deposition

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Nanomanufacturing and Metrology 2022年第3期5卷 191-208页

作者： Jingming zhang yicheng Li Kun Cao Rong Chen State Key Laboratory of Digital Manufacturing Equipment and Technology School of Mechanical Scienceand EngineeringHuazhong Universityof Science and Technology1037 LuoyuRoadWuhan 430074China State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhongUniversityof Science and Technology1037 Luoyu RoadWuhan 430074China

Atomic layer deposition(ALD)is a thin-film fabrication technique that has great potential in nanofabrication.Based on its self-limiting surface reactions,ALD has excellent conformality,sub-nanometer thickness control,and good process compatibility.These merits promote the industrial and research applications of ALD in various fields.This article provides an introduction to ALD and highlights its applications in semiconductors,pan-semiconductors,environment and energy,and other fields.The applications of ALD in the key nodes of integrated circuits are initially demonstrated,and the areaselective ALD technique is discussed as a bottom-up method for self-aligned nanomanufacturing.Emerging applications of ALD are illustrated in the fabrication of passivation layers,functional surface layers,and buffer layers,which have shown the development trend of ALD in miniaturization and diversification.ALD is an enabling technique for atomic and closeto-atomic scale manufacturing(ACSM)of materials,structures,devices,and systems in versatile applications.The use of theory calculation,multiscale simulation,and more novel methods would steer ALD into further evolution,which makes it possible to cater to the demand of ACSM.

关键词： Atomic layer deposition(ALD) Semiconductor Pan-semiconductor Environment and energy

A Comprehensive Review for Micro/Nanoscale Thermal Mapping Technology Based on Scanning Thermal Microscopy

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Journal of Thermal Science 2022年第4期31卷 976-1007页

作者： LI Yifan zhang Yuan LIU yicheng XIE Huaqing YU Wei School of Energy and Materials Shanghai Polytechnic UniversityShanghai 201209China Shanghai Engineering Research Center of Advanced Thermal Functional Materials Shanghai Polytechnic UniversityShanghai 201209China

Thermal characterization becomes challenging as the material size is reduced to micro/nanoscales.Based on scanning probe microscopy(SPM),scanning thermal microscopy(STh M)is able to collect thermophysical characteristics of the microscopic domain with high spatial resolution.Starting from its development history,this review introduces the operation mechanism of the instrument in detail,including working principles,thermal probes,quantitative study,and applications.As the core principle of STh M,the heat transfer mechanism section is discussed emphatically.Additionally,the emerging technologies based on the STh M platform are clearly reviewed and corresponding examples are presented in detail.Finally,the current challenges and future opportunities of STh M are discussed.

关键词： micro/nanoscale thermal mapping scanning thermal microscopy interfacial heat transfer thermoelectrics

Updated developments on molecular imaging and therapeutic strategies directed against necrosis

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Acta Pharmaceutica Sinica B 2019年第3期9卷 455-468页

作者： Dongjian zhang Meng Gao Qiaomei Jin yicheng Ni Jian zhang Affiliated Hospital of Integrated Traditional Chinese and Western Medicine Nanjing University of Chinese MedicineNanjing210028China Laboratories of Translational Medicine Jiangsu Province Academy of Traditional Chinese MedicineNanjing210028China Theragnostic Laboratory Campus GasthuisbergKU LeuvenLeuven3000Belgium

Cell death plays important roles in living organisms and is a hallmark of numerous disorders such as cardiovascular diseases, sepsis and acute pancreatitis. Moreover, cell death also plays a pivotal role in the treatment of certain diseases, for example, cancer. Noninvasive visualization of cell death contributes to gained insight into diseases, development of individualized treatment plans, evaluation of treatment responses, and prediction of patient prognosis. On the other hand, cell death can also be targeted for the treatment of diseases. Although there are many ways for a cell to die, only apoptosis and necrosis have been extensively studied in terms of cell death related theranostics. This review mainly focuses on molecular imaging and therapeutic strategies directed against necrosis. Necrosis shares common morphological characteristics including the rupture of cell membrane integrity and release of cellular contents, which provide potential biomarkers for visualization of necrosis and necrosis targeted therapy. In the present review, we summarize the updated joint efforts to develop molecular imaging probes and therapeutic strategies targeting the biomarkers exposed by necrotic cells. Moreover, we also discuss the challenges in developing necrosis imaging probes and propose several biomarkers of necrosis that deserve to be explored in future imaging and therapy research.

关键词： Necrosis avid agents Exposed DNA Molecular imaging Targeted therapy Solid tumor Myocardial infarction