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A review of optically induced rotation

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Frontiers of Information Technology & Electronic Engineering 2022年第2期23卷 171-185页

作者： Qi ZHU nan li Heming su Wenqiang li Huizhu HU State Key Laboratory of Modern Optical Instrumentation College of Optical Science and EngineeringZhejiang UniversityHangzhou 310027China Zhejiang Lab Hangzhou 311121China

The optical rotation technique arose in the 1990 s.Optical tweezer brought an ideal platform for research on the angular momentum of laser beams.For decades,the optical rotation technique has been widely applied in laboratory optical manipulation and the fields of biology and optofluidics.Recently,it has attracted much attention for its potential in the classical and quantum regimes.In this work,we review the progress of experiments and applications of optically induced rotation.First,we introduce the basic exploration of angular momentum.Then,we cover the development and application of optical rotation induced by orbital angular momentum,and the spin angular momentum is presented.Finally,we elaborate on recent applications of the optical rotation technique in high vacuum.As precise optical manipulation in a liquid medium enters its maturity,optical tweezers in high vacuum open a new path for the high-speed micro-rotor.

关键词： Optical tweezer Optically induced rotation Angular momentum Micro-rotor

Prior austenite grain boundary recognition in martensite microstructure based on deep learning

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Journal of Iron and Steel Research(International) 2023年第5期30卷 1050-1056页

作者： Xuan-dong Wang nan li Hang su Hui-min Meng Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Department of Structural Steel Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China Material Digital R&D Center China Iron&Steel Research Institute Group Co.Ltd.Beijing 100081China Central Laboratory Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China

Grain size determination is essential in producing and testing iron and steel materials.Grain size determination of martensitic steels usually requires etching with picric acid to reveal the prior austenite grain boundaries.However,picric acid is toxic and explosive and belongs to hazardous chemicals,which makes it difficult for laboratories and testing institutions to obtain.A new experimental method was developed to use Nital etchant instead of picric acid.The deep learning method was used to recognize the prior austenite grain boundaries in the etched martensite microstructure,and the grain size could be determined according to the recognition result.Firstly,the polished martensite specimen was etched twice with Nital etchant and picric acid,respectively,and the same position was observed using an optical microscope.The images of the martensitic structure and its prior austenite grain boundary label were obtained,and a data set was constructed.Secondly,based on this data set,a convolutional neural network model with a semantic segmentation function was trained,and the accuracy rate of the test set was 87.53%.Finally,according to the recognition results of the model,the grain size rating can be automatically determined or provide a reference for experimenters,and the difference between the automatic determination results and the measured results is about 0.5 level.

关键词： Prior austenite grain boundary Microstructure etching Image recognition Deep learning

AWSD:An Aircraft Wing Dataset Created by an Automatic Workflow for Data Mining in Geometric Processing

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Computer Modeling in Engineering & Sciences 2023年第9期136卷 2935-2952页

作者： Xiang su nan li Yuedi Hu Haisheng li School of Arti􀀀cial Intelligence Beijing Technology and Business UniversityBeijing100048China School of Computer Science and Engineering Beijing Technology and Business UniversityBeijing100048China

This paper introduces an aircraft wing simulation data set(AWSD)created by an automatic workflow based on creating models,meshing.simulating the wing flight flow field solution,and parameterizing solution results.AWSD is a flexible,independent wing collection of simulations with specific engineering requirements.The data set is applicable to handle computer geometry processing tasks.In contrast to the existing 3D model data set,there are some advantages the scale of this data set is not limited by the collection source,the data files have high quality,no defects,redundancy,and other problems,and the models and simulation are all designed for the specific actual engineering demand.Moreover,AWSD has the characteristics of rich information and a similar model structure,which contributes to the construction of the surrogate model.On the other hand,this data set is suitable for advancing research of data mining in computational geometry graphics.To solve the problem that the CFD flows field results are not intuitive,this paper used the resampling method of surface data to sample the result to the model surface,then segmented the re sampled 3D mesh surface,and compared with the diferences among K-means algorithm,Mini_Batch K means algorithm,and Spectral Clustering algorithm.AWSD provides 300 sets of models,meshes,CFD simulation results,and parametric results based on ARAP(As-Rigid-As Posible)and Harmonic mapping for advancing the construction of engineering surrogate models,3D mesh segmentation,surface resampling,and related geometric processing tasks.

关键词： Dataset CFD mesh parameterization parametric modeling

Machine learning and neural network supported state of health simulation and forecasting model for lithium-ion battery

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Frontiers in Energy 2024年第2期18卷 223-240页

作者： nan QI Kang YAN Yajuan YU Rui li Rong HUANG Lai CHEN Yuefeng su Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China Department of Energy and Environmental Materials School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Electric Vehicle Co. Ltd.Beijing 100176China

As the intersection of disciplines deepens,the field of battery modeling is increasingly employing various artificial intelligence(AI)approaches to improve the efficiency of battery management and enhance the stability and reliability of battery operation.This paper reviews the value of AI methods in lithium-ion battery health management and in particular analyses the application of machine learning(ML),one of the many branches of AI,to lithium-ion battery state of health(SOH),focusing on the advantages and strengths of neural network(NN)methods in ML for lithium-ion battery SOH simulation and prediction.NN is one of the important branches of ML,in which the application of NNs such as backpropagation NN,convolutional NN,and long short-term memory NN in SOH estimation of lithium-ion batteries has received wide attention.Reports so far have shown that the utilization of NN to model the SOH of lithium-ion batteries has the advantages of high efficiency,low energy consumption,high robustness,and scalable models.In the future,NN can make a greater contribution to lithium-ion battery management by,first,utilizing more field data to play a more practical role in health feature screening and model building,and second,by enhancing the intelligent screening and combination of battery parameters to characterize the actual lithium-ion battery SOH to a greater extent.The in-depth application of NN in lithium-ion battery SOH will certainly further enhance the science,reliability,stability,and robustness of lithium-ion battery management.

关键词： machine learning lithium-ion battery state of health neural network artificial intelligence

Activation of autophagy in the retina after optic nerve crush injury in rats

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International Journal of Ophthalmology(English edition) 2019年第9期12卷 1395-1401页

作者： li-Hua Kang su Zhang Sheng Jiang nan Hu Eye Institute Affiliated Hospital of Nantong UniversityNantong 226001Jiangsu ProvinceChina nanjing Medical University Affiliated Eye Hospital Nanjing 210000Jiangsu ProvinceChina

AIM: To investigate the activation of autophagy in rat retina after optic nerve crush(ONC) and evaluate its relationship with apoptosis of retinal ganglion cells(RGCs).METHODS: The ONC model was established. Western blots were performed to investigate expression of p62, LC3 and Beclin-1. Transmission electron microscopy was performed to discover the autophagosomes in the retina after ONC. Immunohistochemistry was used to confirm the distribution of LC3. TUNEL was performed to confirm the relationship between autophagy and RGC apoptosis. REsuLTS: p62/Beclin-1 ratio was declined shortly after ONC until to day 7 after ONC and then restored to a normal level at day 21. There was an opposite change in the LC3-II/LC3 I ratio in the retina compared to the p62/Beclin-1 ratio. Increased autophagosomes were found after ONC using transmission electron microscopy, and most of the LC3-stained cells were colocalized with RGCs and Müller cells. More LC3-immunoreactive cells and apoptotic RGCs were found on day 7 following ONC. CONCLUSION: Possible activation of autophagy in RGCs after ONC;autophagy mainly occurred in RGCs and Müller cells, and the apoptosis of RGCs after ONC may be partly associated with autophagic activation.

关键词： autophagy optic nerve crush apoptosis retinal ganglion cells rat

Fatigue Topology Optimization Design Based on Distortion Energy Theory and Independent Continuous Mapping Method

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Computer Modeling in Engineering & Sciences 2021年第7期128卷 297-314页

作者： Hongling Ye Zonghan li nan Wei Pengfei su Yunkang sui Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing100124China

Fatigue failure is a common failure mode under the action of cyclic loads in engineering applications,which often occurs with no obvious signal.The maximum structural stress is far below the allowable stress when the structures are damaged.Aiming at the lightweight structure,fatigue topology optimization design is investigated to avoid the occurrence of fatigue failure in the structural conceptual design beforehand.Firstly,the fatigue life is expressed by topology variables and the fatigue life filter function.The continuum fatigue optimization model is established with the independent continuous mapping(ICM)method.Secondly,fatigue life constraints are transformed to distortion energy constraints explicitly by taking advantage of the distortion energy theory.Thirdly,the optimization formulation is solved by the dual sequence quadratic programming(DSQP).And the design scheme of lightweight structure considering the fatigue characteristics is obtained.Finally,numerical examples illustrate the practicality and effectiveness of the fatigue optimization method.This method further expands the theoretical application of the ICM method and provides a novel approach for the fatigue optimization problem.

关键词： Fatigue optimization distortion energy theory S-N curve independent continuous mapping method

Dynamic Analysis and Simulation of an Optically Levitated Rotating Ellipsoid Rotor in liquid Medium

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Photonic Sensors 2022年第2期12卷 105-116页

Optical trap,a circularly polarized laser beam can levitate and control the rotation of microspheres in liquid medium with high stiffness.Trapping force performs as confinement while the trapped particle can be analog to a liquid floated gyroscope with three degree-of-ffeedom.In this work,we analyzed the feasibility of applying optically levitated rotor in the system.We presented the dynamic analysis and simulation of an ellipsoid micron particle.The precession motion and nutation motion of a rotating ellipsoid probe particle in optical tweezers were performed.We also analyzed the attitude changes of an optically levitated ellipsoid when there was variation of the external torque caused by deviation of the incident light that was provided.Furthermore,the trail path of the rotational axis vertex and the stabilization process of a particle of different ellipticities were simulated.We compared the movement tendencies of particles of different shapes and analyzed the selection criteria of ellipsoid rotor.These analytical formulae and simulation results are applicable to the analysis of the rotational motion of particles in optical tweezers,especially to the future research of the gyroscope effect.

关键词： Optical Tweezers rotor optically induced rotation dynamic analysis

Signal acquisition of Luojia-1A low earth orbit navigation augmentation system with software defined receiver

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Geo-Spatial Information Science 2022年第1期25卷 47-62页

作者： liang Chen Xiangchen Lu nan Shen Lei Wang Yuan Zhuang Ye su Deren li Ruizhi Chen State Key Laboratory Of Information Engineering In surveying Mapping And Remote SensingWuhan UniversityWuhanChina

Low Earth Orbit(LEO)satellite navigation signal can be used as an opportunity signal in the case of a Global Navigation Satellite System(GNSS)outage,or as an enhancement by means of traditional GNSS positioning algorithms.No matter which service mode is used,signal acquisition is a prerequisite for providing enhanced LEO navigation services.Compared with the medium orbit satellite,the transit time of the LEO satellite is shorter.Thus,it is of great significance to expand the successful acquisition time range of the LEO signal.Previous studies on LEO signal acquisition are based on simulation data.However,signal acquisition research based on real data is crucial.In this work,the signal characteristics of LEO satellites:power space density in free space and the Doppler shift of LEO satellites are individually studied.The unified symbolic definitions of several integration algorithms based on the parallel search signal acquisition algorithm are given.To verify these algorithms for LEO signal acquisition,a Software Defined Receiver(SDR)is developed.The performance of these integration algorithms on expanding the successful acquisition time range is verified by the real data collected from the Luojia-1A satellite.The experimental results show that the integration strategy can expand the successful acquisition time range,and it will not expand indefinitely with the integration duration.The performance of the coherent integration and differential integration algorithms is better than the other two integration algorithms,so the two algorithms are recommended for LEO signal acquisition and a 20 ms integration duration is preferred.The detection threshold of 2.5 is not suitable for all integration algorithms and various integration durations,especially for the Maximum-to-Mean Ratio indicator.

关键词： Coherent integration differential coherent integration Low Earth Orbit(LEO) non-coherent integration navigation augmentation signal acquisition

20(S)-ginsenoside Rh1 alleviates T2DM induced liver injury via the Akt/FOXO1 pathway

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Chinese Journal of Natural Medicines 2022年第9期20卷 669-678页

作者： su Wen-Ya FAN Mei-ling li Ying HU Jun-nan CAI En-Bo ZHU Hong-Yan SONG Ming-Jie li Wei College of Chinese Medicinal Materials Jilin Agricultural UniversityChangchun 130118China Maternity Diagnosis&Treatment Center the Affiliated Hospital of Changchun University of Chinese MedicineChangchun 130021China National&Local Joint Engineering Research Center for Ginseng Breeding and Development Changchun 130118China

Diabetes-associated liver injury becomes a dominant hepatopathy,leading to hepatic failure worldwide.The current study was designed to evaluate the ameliorative effects of ginsenoside Rh1(G-Rh1)on liver injury induced by T2DM.A T2DM model was established using C57BL/6 mice through feeding with HFD followed by injection with streptozotocin at 100 mg·kg^(−1).Then the mice were continuously administered with G-Rh1(5 and 10 mg·kg^(−1)),to explore the protective effects of G-Rh1 against liver injury.Results showed that G-Rh1 exerted significant effects on maintaining the levels of FBG and insulin,and ameliorated the increased levels of TG,TC and LDL-C induced by T2DM.Moreover,apoptosis in liver tissue was relieved by G-Rh1,according to histological analysis.Particularly,in diabetic mice,it was observed that not only the increased secretion of G6Pase and PEPCK in the gluconeogenesis pathway,but also inflammatory factors including NF-κB and NLRP3 were suppressed by G-Rh1 treatment.Furthermore,the underlying mechanisms by which G-Rh1 exhibited ameliorative effects was associated with its capacity to inhibit the activation of the Akt/FoxO1 signaling pathway induced by T2DM.Taken together,our preliminary study demonstrated the potential mechnism of G-Rh1 in protecting the liver against T2DM-induced damage.

关键词： G-Rh1 liver injury Gluconeogenesis PEPCK G6Pase Akt/FOXO1 Inflammation