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Journal of Innovative Optical Health Sciences 2024年第1期17卷 77-86页

作者： yongwei wang Yuyang Wan Zhongjiang Chen MOE Key Laboratory of Laser Life Science&Institute of Laser Life Science South China Normal University Guangzhou 510631P.R.China College of Biophotonics South China Normal University Guangzhou 510631 P.R.China School of Medical Technology and Engineering Fujian Medical University Fuzhou 350004 P.R.China

In this work,we present an intravascular dual-mode endoscopic system capable of both intravascular photoacoustic imaging(IVPAI)and intravascular optical coherence tomography(IVOCT)for recognizing spontaneous coronary artery dissection(SCAD)phantoms.IVPAI provides high-resolution and high-penetration images of intramural hematoma(IMH)at different depths,so it is especially useful for imaging deep blood clots associated with imaging phantoms.IVOCT can readily visualize the double-lumen morphology of blood vessel walls to identify intimal tears.We also demonstrate the capability of this dual-mode endoscopic system using mimicking phantoms and biological samples of blood clots in ex vivo porcine arteries.The results of the experiments indicate that the combined IVPAI and IVOCT technique has the potential to provide a more accurate SCAD assessment method for clinical applications.

关键词： Spontaneous coronary artery dissection(SCAD) intravascular optical coherence tomography(IVOCT) intravascular photoacoustic imaging(IVPAI)

Gypenosides ameliorate morphine-induced immunosuppression with an increased proportion of thymic T lymphocyte subsets and are involved in the regulation of the cAMP-CREM/CREB-IL-2 pathway

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Genes & Diseases 2024年第3期11卷 120-123页

作者： Hui wang Zhonghao Li Qisheng wang Weixin Lin Ziting Zhou Xinru Mu yongwei Jiang Shengfeng Lu Shaodong Chen Zhigang Lu Jiangsu Collaborative Innovation Center of Traditional Chinese Medicine in Prevention and Treatment of Tumor Nanjing University of Chinese MedicineNanjingJiangsu 210023China Key Laboratory of Acupuncture and Medicine Research of Ministry of Education Nanjing University of Chinese MedicineNanjingJiangsu 210023China College of Pharmacy Nanjing University of Chinese MedicineNanjingJiangsu 210023China School of Medicine Xiamen UniversityXiamenFujian 361102China

Opioid abuse can suppress the lymphatic system function,and produce severe immunosuppression that poses a significant risk of opportunistic infections such as methicillinresistant Staphylococcus aureus(MRSA)pneumonia.^(1,2)Gypenosides(Gps)are the most important immunomodulator components in the Chinese herbal medicine Gynostemma pentaphyllum.

关键词： herbal Gypenosides immunosuppression

Learning Label Correlations for Multi-Label Online Passive Aggressive Classification Algorithm

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Wuhan University Journal of Natural Sciences 2024年第1期29卷 51-58页

作者： ZHANG yongwei Nanjing NARI Intelligent Transport Technology Co. Ltd.Nanjing 210061JiangsuChina

Label correlations are an essential technique for data mining that solves the possible correlation problem between different labels in multi-label classification.Although this technique is widely used in multi-label classification problems,batch learning deals with most issues,which consumes a lot of time and space resources.Unlike traditional batch learning methods,online learning represents a promising family of efficient and scalable machine learning algorithms for large-scale datasets.However,existing online learning research has done little to consider correlations between labels.On the basis of existing research,this paper proposes a multi-label online learning algorithm based on label correlations by maximizing the interval between related labels and unrelated labels in multi-label samples.We evaluate the performance of the proposed algorithm on several public datasets.Experiments show the effectiveness of our algorithm.

关键词： label correlations passive aggressive multi-label classification online learning

Debris Flow Susceptibility Evaluation in Meizoseismal Region:A Case Study in Jiuzhaigou,China

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Journal of Earth Science 2024年第1期35卷 263-279页

作者： yongwei Li Linrong Xu Yonghui Shang Shuyang Chen School of Civil Engineering Central South UniversityChangsha 410075China National Engineering Research Center of High-Speed Railway Construction Technology Central South UniversityChangsha 410075China School of Civil Engineering Central South University of Forestry and TechnologyChangsha 410004China

Jiuzhaigou is situated on a mountain-canyon region and is famous for frequent tectonic activities.An abundance of loose co-seismic landslides and collapses were produced on gullies after the Jiuzhaigou Earthquake on August 8,2017,which was served as material source for debris flow in later years.Debris flow appears frequently which are seriously endangering the safety of people's lives and properties.Even the earliest debris flow appeared in areas where no case ever reported before.The debris flow susceptibility evaluation(DFSE)is used for predicting the areas prone to debris flow,which is urgently required to avoid hazards and help to guide the strategy of preventive measures.Therefore,this work employs debris flow in Jiuzhaigou to reveal the characteristics of disaster-pregnant environment and to explore the application of machine learning in DFSE.Some new viewpoints are suggested:(i)Material density factor of debris flow is first adopted in this work,and it is proved to be a critical factor for triggering debris flows by sensitivity analysis method.(ii)Deep neural network and convolutional neural network(CNN)achieve relatively good area under the curve(AUC)values and are 0.021-0.024 higher than traditional machine learning methods.(iii)Watershed units combined with CNNbased model can achieve more accurate,reliable and practical susceptibility map.This work provides an idea for prevention of debris flow in mountainous lands.

关键词： machine learning earthquakes debris flow susceptibility convolutional neural network deep neural network watershed unit

Effect of Using Land Use Data with Building Characteristics on Urban Weather Simulations:A High Temperature Event in Shanghai

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Journal of Meteorological Research 2022年第6期36卷 900-913页

作者： Dahu YANG yongwei wang Caijun YUE School of Atmospheric Physics Nanjing University of Information Science&TechnologyNanjing 210044 Shanghai Marine Meteorological Center Shanghai 200030

Land use data with building characteristics are important for modeling the impacts of urban morphology on local climate.In this study,an extreme heat event in Shanghai,China,was simulated by using a WRF/BEP+BEM(Weather Research and Forecasting/Building Effect Parameterization+Building Energy Model)model.We incorporated local climate zone(LCZ)land use data that resolved urban morphology using 10 classes of building parameters.The simulation was compared to a control case based on MODIS(Moderate-resolution Imaging Spectroradiometer)land use data.The findings are as follows:(1)the LCZ data performed better than the MODIS data for simulating 10-m wind speed.An increase in building height led to the wind speed to decrease by 0.6-1.4 m s^(-1)in the daytime and by 0.2-0.7 m s^(-1)at nighttime.(2)High-rise buildings warmed the air by trapping radiation in the urban canyon.This warming effect was partially offset by the cooling effect of building shadows in the day.As a result,the 2-m temperature increased by 0.8℃ at night but only by 0.4℃ during the day.(3)Heterogeneous urban surfaces increased the 50-m turbulent kinetic energy by 0.4 m^(2) s^(-2),decreased the 10-m wind speed by 1.8 m s^(-1)in the daytime,increased the surface net radiation by 45.1 W m^(2)-,and increased the 2-m temperature by 1.5℃ at nighttime.(4)The LCZ data modified the atmospheric circulation between land and ocean.The shadowing effect reduced the air temperature differences between land and ocean and weakened the sea breeze.Moreover,high-rise buildings obstructed sea breezes,restricting their impact to a smaller portion(10 km along the wind direction)of inland areas compared to that with MODIS.

关键词： local climate zone Weather Research and Forecasting model characteristics of building parameters high temperature

Simulation of Two-Phase Flowback Phenomena in Shale Gas Wells

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Fluid Dynamics & Materials Processing 2024年第2期20卷 349-364页

作者： yongwei Duan Zhaopeng Zhu Hui He Gaoliang Xuan Xuemeng Yu Oil Gas Engineering Research Institute PetroChina Jilin OilfieldSongyuan138000China

The gas-water two-phaseﬂow occurring as a result of fracturingﬂuidﬂowback phenomena is known to impact signiﬁcantly the productivity of shale gas well.In this work,this two-phaseﬂow has been simulated in the framework of a hybrid approach partially relying on the embedded discrete fracture model(EDFM).This model assumes the region outside the stimulated reservoir volume(SRV)as a single-medium while the SRV region itself is described using a double-medium strategy which can account for theﬂuid exchange between the matrix and the micro-fractures.The shale gas adsorption,desorption,diffusion,gas slippage effect,fracture stress sensitivity,and capillary imbibition have been considered.The shale gas production,pore pressure distribution and water saturation distribution in the reservoir have been simulated.The inﬂuences of hydraulic fracture geometry and nonorthogonal hydraulic fractures on gas production have been determined and discussed accordingly.The simulation results show that the daily gas production has an upward and downward trend due to the presence of a large amount of fracturingﬂuid in the reservoir around the hydraulic fracture.The smaller the angle between the hydraulic fracture and the wellbore,the faster the daily production of shale gas wells decreases,and the lower the cumulative production.Nonplanar fractures can increase the control volume of hydraulic fractures and improve the production of shale gas wells.

关键词： Shale gas fracturingﬂuid backﬂow the stimulated reservoir volume gas-water two-phase production

Mechanism of the electromagnetic force to control hydrodynamic noise from an airfoil model and its action mode

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Chinese Journal of Acoustics 2024年第2期43卷 173-198页

作者： LIU yongwei wang Lu QIN Qikai ZHENG Penghui SHANG Dejiang National Key Laboratory of Underwater Acoustic Technology Harbin Engineering UniversityHarbin 150001 Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001 College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001

A method is proposed to control the flow and reduce the hydrodynamic noise by applying the constant electromagnetic force into the boundary layer. The flow and sound fields from an airfoil model with and without the electromagnetic force are calculated. Results show that along the flow direction, electromagnetic force can delay the flow separation on the airfoil surface, suppress small discrete vortices, reduce turbulent fluctuation pressure on the airfoil surface, and decrease the hydrodynamic noise. The change law of the hydrodynamic noise effect reduced by the electromagnetic force is summarized in terms of the Reynolds number, attack angle, and electromagnetic effective parameters.Based on the numerical calculation results, an actual model is experimentally measured in the water circulating tank to validate the abovementioned effect. Since the transition area pressure of the airfoil model is the lowest and the area is limited, the application of electromagnetic force into this area can achieve the lowest noise effect and decrease the power consumption. The effect of the magnetic leak is analyzed. The results provide a new method for the suppression of hydrodynamic noise in airfoil models.

关键词： airfoil noise flow

Design and application of the dynamic detection platform for testing the micromechanical properties of agricultural products

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International Journal of Agricultural and Biological Engineering 2022年第6期15卷 8-15页

作者： Yifeng Hao yongwei wang Qianjing Jiang Jing Zhang Jun wang Department of Biosystems Engineering Zhejiang UniversityHangzhou 310058China Key Laboratory of Intelligent Equipment and Robotics for Agriculture of Zhejiang Province Hangzhou 310058China

The micromechanical properties of agricultural products can be used to formulate simulation models and optimize processing parameters for harvest,packaging,and storage.In this study,a detection platform was designed for conducting mechanical tests on different specimens at the tissue level.The system provided controllable and precise displacements;the relative error was less than±1.0%.The displacement and force measurements were calibrated.Micromechanical tests of apple parenchyma tissues were conducted to evaluate the performance of the proposed platform.The stress-strain curves of the specimens and the micrographs of the microstructures can be obtained simultaneously during the tests.The proposed platform has the capability to test mechanical properties and obtain micro behaviors of agricultural products at the tissue level,which helps in studying the failure mechanism of agricultural products under external loading.

关键词： elasticity module micro tensile parenchyma tissue micromechanical properties agricultural products

Experiment and parameter optimization of an automatic row following system for the traction beet combine harvester

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International Journal of Agricultural and Biological Engineering 2023年第1期16卷 145-152页

作者： Shenying wang Xuemei Gao Zhaoyan You Baoliang Peng Huichang Wu Zhichao Hu yongwei wang Nanjing Institute of Agricultural Mechanization Ministry of Agriculture and Rural AffairsNanjing 210014China College of Biosystems Engineering and Food Science Zhejiang UniversityHangzhou 310058China Key Laboratory of Intelligent Equipment and Robotics for Agriculture of Zhejiang Province Hangzhou 310058China

To improve the automation level and operation quality of China's beet harvester and reduce the loss due to damaged and missed excavation,this study used a self-developed sugar beet combine harvester and field simulation experiment platform,based on the single-factor bench test of the automatic row following system in the early stage,taking hydraulic flow A,spring preload B,and forward speed C which have significant influence on performance indices as test factors,and taking the missed excavation rate,breakage rate and reaction time as performance indices,the orthogonal experimental study on the parameter optimization of the three-factor and three-level automatic row following system with the first-order interaction of various factors was carried out.The results of the orthogonal experiments were analyzed using range analysis and variance analysis.The results showed that there were differences in the influence degree,factor priority order and first-order interaction,and the optimal parameter combination on each performance index.A weighted comprehensive scoring method was used to optimize and analyze each index.The optimal parameter combination of the overall operating performance of the automatic row following system was A 2B 2C 1,that is,the hydraulic flow was 25 L/min,the forward speed was 0.8 m/s,and the spring preload was 198 N.Under this combination,the response time was 0.496 s,the missed excavation rate was 2.35%,the breakage rate was 3.65%,and the operation quality was relatively good,which can meet the harvest requirements.The comprehensive optimization results were verified by field experiments with different ridge shapes and different planting patterns.The results showed that the mean values of the missed excavation rate of different planting patterns of conventional straight ridges and extremely large"S"ridges were 2.23%and 2.69%,respectively,and the maximum values were 2.39%and 2.98%,respectively;the average damage rates were 3.38%and 4.14%,and the maximum values were 3.58%and 4.48%,which meet the in

关键词： beet combine harvester traction type parameter optimization automatic row following

Design and modelling of the full-feed peanut picking device with selfadaptive adjustable working clearance and feeding rate

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International Journal of Agricultural and Biological Engineering 2023年第6期16卷 97-106页

作者： Shenying wang Baoliang Peng Huichang Wu Zhichao Hu Dawei Sun yongwei wang Mingzhu Cao College of Biosystems Engineering and Food Science Zhejiang UniversityHangzhou 310058China Nanjing Institute of Agricultural Mechanization Ministry of Agriculture and Rural AffairsNanjing 210014China Key Laboratory of Intelligent Equipment and Robotics for Agriculture of Zhejiang Province Hangzhou 310058China Key Laboratory of Agricultural Equipment for Hilly and Mountainous Areas in Southeastern China(Co-construction by Ministry and Province) Ministry of Agriculture and Rural AffairsHangzhou 310058China

To improve the declining performance of a full-feed peanut picking device or solve the mechanical failures that occur due to fluctuations in the feeding rate during operation,the 4HLJI-3000 peanut intelligent picking combine harvester,which is a picking device with a self-adaptive adjustment of the working clearance,was developed as the research object in this study.Moreover,the key components,such as the picking roller,concave plate sieve and clearance adjustment mechanism of the concave plate sieve,were designed and analysed.Through the force analysis of the concave plate sieve of the picking device,the mathematical model of the concave plate sieve displacement of the picking device and feeding rate was obtained.The software system for monitoring,storing and analysing the concave plate sieve displacement of the picking device based on EasyBuilder Pro was designed,and the road monitoring test of displacement variation of concave plate sieve of the picking device and feeding rate was carried out.The linear function,power function,exponential function,quadratic function,compound function,logarithmic function and cubic function fitting were used to perform regression analysis of the test results by using IBM SPSS software.The results showed that the cubic function model had a higher fitting precision,and its determination coefficient was 0.992.Model verification experiments were proposed,and the results showed that the established cubic function model had a good accuracy.The absolute deviation rate ranged from 0 to 4.83%,and the average deviation rate was 2.22%.The deviation rate increased with an increasing feeding rate.The field experiments also proved that there was a cubic function relationship between the feeding rate and concave plate sieve displacement,the measured concave plate sieve displacement deviation rate ranged from 0 to 6.19%,and the average deviation rate was 2.73%compared with the calculated results.This study can provide a reference for the optimization design of the structure of full-feeding pic

关键词： agricultural machinery peanut picking device feeding rate concave plate sieve displacement EasyBuilder