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深度学习在心力衰竭检测中的应用综述

计算机科学与探索 2025年第1期19卷 65-78页

作者：王永威魏德健曹慧姜良山东中医药大学智能与信息工程学院济南250355

随着生物医学技术的发展,利用生物信号进行心力衰竭的早期诊断已成为提高患者生存率和降低治疗成本的关键策略。在此背景下,深度学习技术的迅猛发展为心力衰竭检测开辟了新路径。系统地综述了深度学习在心力衰竭检测中的最新进展和应用... 详细信息

随着生物医学技术的发展,利用生物信号进行心力衰竭的早期诊断已成为提高患者生存率和降低治疗成本的关键策略。在此背景下,深度学习技术的迅猛发展为心力衰竭检测开辟了新路径。系统地综述了深度学习在心力衰竭检测中的最新进展和应用。概述了心力衰竭检测涉及的主要生物医学信号和公开数据集。详细分析了深度学习在心力衰竭诊断领域的应用及其发展,特别是对卷积神经网络和长短期记忆网络处理心电图、心率变异性、心音等关键生物医学信号的能力进行了深入分析,总结了这些技术的优势、局限性,并对各类模型性能进行了比较。探讨了通过融合多种人工智能技术所构建的混合模型在提升检测精度和模型泛化能力方面的潜力,以及如何利用模型的可解释性来增加检测过程的透明度,提升医生的信任度。最后总结了当前研究存在的不足,并对未来研究方向提出展望,强调了跨学科合作在推动心力衰竭检测技术进步中的重要性。

关键词：心力衰竭生物医学信号深度学习卷积神经网络循环神经网络混合模型

Large-eddy Simulation of Fluid Flow and Heat Transfer in a Mixing Tee Junction

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Chinese Journal of Mechanical Engineering 2012年第6期25卷 1144-1150页

作者： LU Tao wang yongwei wang Kuisheng School of Mechanical and Electrical Engineering Beijing University of Chemical TechnologyBeijing 100029China

The temperature fluctuation caused by thermal striping phenomena of hot and cold fluids mixing results in cyclical thermal stress fatigue failure of the pipe wall. Mean temperature difference between hot and cold fluids was often used as thermal load in previous analysis of thermal fatigue failure, thereby the influences of the amplitude and frequency of temperature fluctuation on thermal fatigue failure were neglected. Based on the mechanism of flow and heat transfer which induces thermal fatigue, the turbulent mixing of hot and cold water in a tee junction is simulated with FLUENT platform by using the Large-eddy simulation（LES） turbulent flow model with the sub-grid scale（SGS） model of Smagorinsky-Lilly（SL） to capture the amplitude and frequency of temperature fluctuation. In a simulation case, hot water with temperature of 343.48 K and velocity of 0.15 m/s enters the horizontal main duct with the side length of 100 mm, while cold water with temperature of 296.78 K and velocity of 0.3 m/s enters the vertical branch duct with the side length of 50 mm. The numerical results show that the mean and fluctuating temperatures are in good agreement with the previous experimental data, which describes numerical simulation with high reliability and accuracy; the power spectrum density（PSD） on top wall is higher than that on bottom wall（as the frequency less than 1 Hz）, while the PSD on bottom wall is relatively higher than that on top wall （as the frequency of 1-10Hz）. The temperature fluctuations in full mixing region of the tee junction can be accurately captured by LES and can provide the theoretical basis for the thermal stress and thermal fatigue analyses.

关键词： Large-eddy simulation flow heat transfer tee junction

A Hybrid Local/Nonlocal Continuum Mechanics Modeling and Simulation of Fracture in Brittle Materials

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Computer Modeling in Engineering & Sciences 2019年第11期121卷 399-423页

作者： yongwei wang Fei Han Gilles Lubineau King Abdullah University of Science and Technology(KAUST) Physical Science and Engineering DivisionCOHMAS LaboratoryThuwal23955-6900Saudi Arabia State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsInternational Research Center for Computational MechanicsDalian University of TechnologyDalian116023China

Classical continuum mechanics which leads to a local continuum model,encounters challenges when the discontinuity appears,while peridynamics that falls into the category of nonlocal continuum mechanics suffers from a high computational cost.A hybrid model coupling classical continuum mechanics with peridynamics can avoid both *** paper describes the hybrid model and its adaptive coupling approach which dynamically updates the coupling domains according to crack propagations for brittle *** this hybrid local/nonlocal continuum model is applied to fracture *** numerical examples like a plate with a hole,Brazilian disk,notched plate and beam,are performed for verification and *** addition,a peridynamic software is introduced,which was recently developed for the simulation of the hybrid local/nonlocal continuum model.

关键词： Peridynamics hybrid model adaptive coupling fracture simulation morphing function numerical discretization

Numerical study of collection efficiency and heat-transfer characteristics of packed granular filter

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Particuology 2019年第5期17卷 75-82页

作者： Junlin Chen Xunfeng Li Xiulan Huai yongwei wang Jingzhi Zhou Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

The collection mechanism and heat-transfer characteristics of a packed granular filter were investigated using a three-dimensional randomly packed granular filter model. The bridging method was introduced to optimize the grids of contact points between granules. The influences of granular bed depth, gas velocity, and gas temperature on grade collection efficiency were investigated. The results indicated that a decrease of temperature improved collection efficiency when the particle diameter was greater than 5 |xm. The grade collection efficiency maintained a stable value when the Stokes number, St, was less than 0.009, but increased linearly with ig(St) when St > 0.009. A logarithmic mean temperature difference method was used to obtain overall heat-transfer coefficients of gas-solid two-phase flow through the packed granular filter. The results showed that convective heat transfer was enhanced due to the intro-duction of solid particles in the bed. The overall heat-transfer coefficient increased approximately linearly with an increase in particle loading ratio. The Nusselt number was related to the Reynolds number, the Archimedes number, and the particle loading ratio.

关键词： Packed granular filter Gas-solid two-phase flow Grade collection efficiency Heat transfer

Ultrathin lanthanide oxides nanomaterials： synthesis, properties and applications

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Science Bulletin 2016年第18期61卷 1422-1434页

作者： Xinyu Zhang yongwei wang Fenghua Cheng Zhiping Zheng Yaping Du Frontier Institute of Science and Technology Jointly with College of Science State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Xi'an 710049China Collegeof Material-and Chemical Engineering Zhengzhou University of Light Industry Zhengzhou 450002 China Department of Chemistry and Biochemistry The University of Arizona Tucson AZ 85721-0041 USA

Over the past decade, ultrathin lanthanide oxides （Ln2O3, Ln = La to Lu） nanomaterials have been intensively studied in the fields of rare earth materials science. This unique class of nanomaterials has shown many unprecedented properties （big surface area, high surface effect, physical and chemical activities） and is thus being explored for numerous promising applications. In this review, a brief introduction of ultrathin Ln2O3 nanomaterials was given and their unique advantages were highlighted. Then, the typical synthetic methodologies were summarized and compared （thermal decomposition, solvothermal, soft template, co-precipition and microwave etc.）. Due to the high surface effect, some promising applications of ultmthin Ln203 nanomaterials, such as drug delivery and catalysis of CO oxidation, were reviewed. Finally, on the basis of current achievements on ultrathin Ln203 nanomaterials, personal perspectives and challenges on future research directions were proposed.

关键词： Lanthanide oxides Ultrathin nanostructures Synthetic strategies Surface related proptries Drug delivery Catalysis

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 *** this study,a detection platform was designed for conducting mechanical tests on different specimens at the tissue *** system provided controllable and precise displacements;the relative error was less than±1.0%.The displacement and force measurements were *** tests of apple parenchyma tissues were conducted to evaluate the performance of the proposed *** stress-strain curves of the specimens and the micrographs of the microstructures can be obtained simultaneously during 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

Diurnal and Seasonal Variations of Thermal Stratification and Vertical Mixing in a Shallow Fresh Water Lake

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Journal of Meteorological Research 2018年第2期32卷 219-232页

作者： Yichen YANG yongwei wang Zhen ZHANG Wei wang Xia REN Yaqi GAO Shoudong LIU Xuhui LEE Yale–NUIST Center on Atmospheric Environment Nanjing University of Information Science & Technology School of Environmental Science and Engineering Nanjing University of Information Science & Technology School of Atmospheric Physics Nanjing University of Information Science & Technology School of Applied Meteorology Nanjing University of Information Science & Technology School of Forestry and Environmental Studies Yale University

Among several influential factors, the geographical position and depth of a lake determine its thermal structure. In temperate zones, shallow lakes show significant differences in thermal stratification compared to deep lakes. Here,the variation in thermal stratification in Lake Taihu, a shallow fresh water lake, is studied systematically. Lake Taihu is a warm polymictic lake whose thermal stratification varies in short cycles of one day to a few days. The thermal stratification in Lake Taihu has shallow depths in the upper region and a large amplitude in the temperature gradient,the maximum of which exceeds 5°C m–1. The water temperature in the entire layer changes in a relatively consistent manner. Therefore, compared to a deep lake at similar latitude, the thermal stratification in Lake Taihu exhibits small seasonal differences, but the wide variation in the short term becomes important. Shallow polymictic lakes share the characteristic of diurnal mixing. Prominent differences on the duration and frequency of long-lasting thermal stratification are found in these lakes, which may result from the differences of local climate, lake depth, and fetch. A prominent response of thermal stratification to weather conditions is found, being controlled by the stratifying effect of solar radiation and the mixing effect of wind disturbance. Other than the diurnal stratification and convection, the representative responses of thermal stratification to these two factors with contrary effects are also discussed. When solar radiation increases, stronger wind is required to prevent the lake from becoming stratified. A daily average wind speed greater than 6 m s–1 can maintain the mixed state in Lake Taihu. Moreover, wind-induced convection is detected during thermal stratification. Due to lack of solar radiation, convection occurs more easily in nighttime than in daytime. Convection occurs frequently in fall and winter, whereas long-lasting and stable stratification causes less co

关键词： Lake Taihu thermal stratification solar radiation wind speed convection

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 ***,the key components,such as the picking roller,concave plate sieve and clearance adjustment mechanism of the concave plate sieve,were designed and *** 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 *** 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 *** 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 *** results showed that the cubic function model had a higher fitting precision,and its determination coefficient was *** verification experiments were proposed,and the results showed that the established cubic function model had a good *** 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 *** 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 *** study can provide a reference for the optimiza

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

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 *** results of the orthogonal experiments were analyzed using range analysis and variance *** 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 *** 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 *** 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 *** comprehensive optimization results were verified by field experiments with different ridge shapes and different planting *** 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 maxi

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