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Numerical and experimental studies on the carcass characteristics of a radial tire

PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART D-JOURNAL OF AUTOMOBILE ENGINEERING 2024年第8期238卷 2133-2145页

作者： Qian, Chao Sun, Pengfei Zhou, Shuiting chen, luwen Su, Guoyun Sun, Xin Xiamen Univ Technol Sch Mech & Automot Engn Xiamen 361021 Fujian Peoples R China

In this research, the carcass characteristics of a radial tire were analyzed by performing numerical simulations on ABAQUS software based on the single factor control variable method, and the feasibility of the proposed numerical model was verified by executing experiments on a tire uniformity testing machine. It was found that when the tire crossed the bump, the preload had positive effects on the internal energies and friction-dissipation fluctuation of the tire, but had little influence on its kinetic energy fluctuation. Tire speed was positively correlated with the fluctuation of kinetic energy, but negatively correlated with the friction-dissipation fluctuation of the tire. In addition, there was a slight correlation between the speed and the internal energy fluctuation of the tire. Moreover, the change in the tire pressure had little influence on the kinetic energy, internal energy, and friction dissipation of the tire.

关键词： Transient response carcass characteristics radial tire ABAQUS bump

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Metagenomic deciphers the mobility and bacterial hosts of antibiotic resistance genes under antibiotics and heavy metals co-selection pressures in constructed wetlands

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ENVIRONMENTAL RESEARCH 2025年 269卷 120921页

作者： Yu, Meng-Fei chen, luwen Liu, Guihua Liu, Wenzhi Yang, Yuyi Ma, Lin South Cent Minzu Univ Coll Life Sci Key Lab Biotechnol State Ethn Affairs Commiss Wuhan Peoples R China Chinese Acad Sci Key Lab Aquat Bot & Watershed Ecol Wuhan Bot Garden Wuhan Peoples R China Chinese Acad Sci Hubei Key Lab Wetland Evolut & Ecol Restorat Wuhan Peoples R China

Both antibiotics and heavy metals exert significant selection pressures on antibiotic-resistance genes (ARGs). This study aimed to investigate the co-selection effects of doxycycline (DC) and cadmium (Cd) on ARGs in constructed wetlands (CWs). The results demonstrated that under antibiotic and heavy metal co-selection pressures, single high concentration DC/Cd or double high, relative abundances of metagenomics assembled genomes all reached 55.1%;meanwhile, the average ratio of ARG-containing contigs located on chromosomes was 61.8% (ranging from 50.4% to 70.6%) suggesting a more stable inheritance of ARGs. Antibiotic and heavy metal co-selection in single high concentration DC/Cd or double high groups stimulate the enrichment of ARG host bacteria, which exhibited complex multiple-resistant patterns accompanied by a host-specific pattern. Additionally, the potential transfer abilities of ARGs mediated by plasmids and integrative and conjugative elements (ICEs) were enhanced under single high-concentration DC/Cd or double high stresses. Together, antibiotic and heavy metal co-selection pressures increased occurrence frequencies of ARGs, MGEs, and their combinations and altered structural communities of ARG host bacteria, increasing the risk of the spread of ARGs. This study was helpful in understanding the dissemination of ARGs and simultaneously preventing the spread of heavy metal-resistant bacteria and ARGs under antibiotic and heavy metal co-selection in small- and micro-wetlands.

关键词： Antibiotic resistance genes Antibiotic and heavy metal co-selection Constructed wetlands Mobile genetic elements

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Pathways of VR+Music Combination Therapy to Intervene in the Emotions of Patients with Mental Disorders

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Applied Mathematics and Nonlinear Sciences 2024年第1期9卷

作者： chen, luwen Zhang, Mengni School of Music Wenzhou University Zhejiang Wenzhou325000 China Wuhan Conservatory Of Music Hubei Wuhan430060 China

This paper proposes a path strategy for VR+music combination therapy in future development and introduces an emotion recognition model based on EEG signals to address its inability to quantify the therapeutic effect of emotional intervention. EEG signal feature extraction involves extracting the differential entropy of the signal as a feature and smoothing it in a time series using a linear dynamic system. On this basis, the SVN-KNN-based emotion EEG recognition algorithm is further proposed, and the KNN algorithm is weighted and adjusted by using the inter-class sample density, which avoids the interference of the imbalanced distribution of the number of samples on the performance of the classifier and improves the generalization ability of the classification model. In the VR+music combination therapy experiment, the PSD of the theta, alpha, and beta EEG bands of the patients in the observation group was higher than that before the experiment. The difference between the observation group and the control group in the CERQ-C scores after the experiment in the factors of self-blame, contemplation, blaming others, acceptance, and rational analysis was statistically highly significant (P © 2024 luwen chen et al., published by Sciendo.

关键词： Emotion Recognition

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The influence of aerosols on lightning activity in the Pearl River Delta of China

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ATMOSPHERIC RESEARCH 2025年 321卷

作者： Zhang, Zebiao Deng, Tao Zhang, Xue Huang, Hanjie He, Guowen Tang, chenguang chen, luwen Leung, Jeremy Cheuk-Hin Xiao, Hui Ouyang, Shanshan Wang, Qing Rao, Gongke Wu, Dui Wu, cheng Jinan Univ Inst Environm & Climate Res Coll Environm & Climate Guangzhou 510632 Peoples R China GBA Acad Meteorol Res Guangzhou Inst Trop & Marine Meteorol Guangdong Prov Key Lab Reg Numer Weather Predict China Meteorol Adm Guangzhou 510640 Peoples R China Sun Yat Sen Univ Sch Atmospher Sci Zhuhai 519082 Peoples R China Southern Univ Sci & Technol Sch Environm Sci & Engn Shenzhen 518055 Peoples R China

Investigating the interaction mechanisms between aerosols and lightning activity is a critical scientific issue in understanding the coupling of urban atmospheric environments with regional weather, holding significant value for extreme weather warnings and climate change adaptation. However, recent studies rarely explain the mechanisms of aerosol impacts on lightning activity from the perspective of atmospheric vertical structure. To address this gap, this study conducted an integrated analysis of multi-source observational data (aerosols, cloud-to-ground (CG) lightning, atmospheric thermodynamic factors, and cloud-related parameters) in the Pearl River Delta (PRD) over nine years (2013-2021). It was found that regions with high aerosol loads in the PRD exhibit a strong spatio-temporal correlation with areas of intense lightning activity. If aerosol influences are considered, the convective available potential energy (CAPE) can better account for the variations in lightning activity peaks during specific years. At the same time, strong convective conditions accelerate the shift of aerosols from enhancing to suppressing lightning activity. From the perspective of atmospheric vertical structure, as conditions transition from clean to polluted, the aerosol-cloud interaction (ACI) mechanism significantly increases cloud particle density by up to 300 %. This not only facilitates the electrification process of thunderclouds but also affects the atmospheric temperature gradient at corresponding altitudes. In polluted conditions (with aerosol optical depth (AOD) > 0.75), the temperature gradient in the middle and upper troposphere decreases by more than 0.5 degrees C. This enhances the development of inversion layers, thereby increasing atmospheric stability and suppressing convection and subsequent lightning activity. The above findings demonstrate that the promoting and inhibiting effects of aerosols on lightning differ under clean and polluted conditions.

关键词： Aerosol Lightning Convective intensity Cloud particles ACI

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Analysis of cord stress during tire dynamic longitudinal slip

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JOURNAL OF INDUSTRIAL TEXTILES 2023年 53卷

作者： chen, luwen Sun, Pengfei Zhou, Shuiting Meng, Junling Qian, Chao Sun, Xin Xiamen Univ Technol Sch Mech & Automot Engn Xiamen 361024 Peoples R China

Selected 215/55 R17 radial tires for material test to obtain relevant material parameters. Used these parameters to build a finite element model and conduct longitudinal slip simulation. The relationship between longitudinal force and slip rate at different speeds and loads was determined by tire longitudinal slip tests. Then the longitudinal slip simulation results were compared with the test results to verify the feasibility of the model. The circumferential and axial rebar force of the belt layer at different speeds and the extreme value of the circumferential rebar force on the reverse-envelope of different skeleton materials were analyzed. The results show that: in the static state, the cord force of the belt layer had shown a trend consistent with the direction of the cord arrangement. As the speed increased, the belt cord force exhibited significant fluctuations and asymmetry. The rebar force of the turn-up points on the belt and ply is significantly smaller compared to the fetal crown ply. The rebar force at the fetal crown and belt wrapping points at 60 km/h was smaller than at 40 km/h and 80 km/h. The cord force of the fetal crown ply and the belt ply is much more affected by the load than that of the ply.

关键词： Radial tire finite element method tire cord slip ratio rebar force rubber and nylon textiles

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Optimization of tire-ground performance through meshed belt layer structure

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JOURNAL OF INDUSTRIAL TEXTILES 2024年 54卷

作者： Mao, Rui Sun, Pengfei Zhou, Shuiting chen, luwen Meng, Junling Yang, Wenqi Yang, chenyi Luo, Kejie Xiamen Univ Technol Sch Automot & Mech Engn Xiamen Peoples R China Xiamen Univ Technol Sch Mech & Automot Engn Xiamen 361024 Peoples R China

Using Abaqus finite element software, this study investigates the impact of different carcass belt layer structures on the grounding characteristics of tires. Focusing on the 215/55R17 radial tire, the research proposes a structural optimization scheme and establish a finite element model. The standard tire belt layer structure is replaced with a mesh belt layer structure to achieve optimized performance. Through static loading tests on the tire, the accuracy of the finite element model was validated. By altering the density, number of layers of the mesh belt structure, and radial load of the tire, a simulation analysis is conducted to study the impact on tire deformation and stress on the carcass material. The optimized tire features increased radial stiffness and reduced tread wear. The density of the mesh belt layer in the contact area affects tire deformation as well as the stress on the belt layer and ply layer. The results indicate that the mesh belt layer can effectively absorb the radial load of the tire, optimizing tire deformation by 20% to 30%. Under different loads, the tire with a 70-density mesh belt layer can reduce surface stress by approximately 40%, or around 230J. The mesh belt layer tire can reduce the sensitivity of the tire center to high load stresses, optimizing 25% of the concentrated stress at the shoulder position of the ply layer. When a double-layer belt is used, the strength at the shoulder increases with the number of belt layers, reducing stress by approximately 2-4N. The structural form of the belt layer has little impact on the trend of stored strain energy changes, but the number of belt layers significantly affects the amount of change in the tire's strain energy. On average, about 10% of the stored strain energy is reduced due to changes in the belt layer structure.

关键词： Textile experiments mesh structure tire belt layer tire ground contact performance rubber and nylon textiles Finite element method

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Climatology of Large Peak Current Cloud-to-Ground Lightning Flashes in China's Most Populous Areas

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EARTH AND SPACE SCIENCE 2023年第10期10卷

作者： Wang, Fei Zhang, Yijun chen, luwen Zhang, Yang Yao, Wen Zheng, Dong Chinese Acad Meteorol Sci State Key Lab Severe Weather Beijing Peoples R China Chinese Acad Meteorol Sci CMA Key Lab Lightning Beijing Peoples R China Fudan Univ Dept Atmospher & Ocean Sci Shanghai Peoples R China Fudan Univ Inst Atmospher Sci Shanghai Peoples R China Fudan Univ Ctr Atmosphere Ocean Interact Shanghai Key Lab Ocean Land Atmosphere Boundary Dy Shanghai Peoples R China Fudan Univ Ctr Atmosphere Ocean Interact Shanghai Frontiers Sci Shanghai Peoples R China China Meteorol Adm Inst Trop & Marine Meteorol Guangzhou Peoples R China

Using a 10-year data set of cloud-to-ground lightning (CG) flashes, the climatological characteristics of +/- CG flashes with a large peak current (>75 kA or <-75 kA) (+/- LPCCGs) are for the first time obtained in China's most populous areas in terms of density distribution, seasonal variation, and monthly and diurnal evolution. The results show that the distribution of +LPCCG flashes has evident seasonal variations, while the activity center of -LPCCG flashes always remains in Southwest China. The diurnal evolution of +LPCCG flash percentages in southern China's Mainland shows an opposite trend to that in the north. Furthermore, the peak current distributions of +LPCCG flashes in most of China's mainland are found to be distinct from those shown in other regions of the world. Additionally, Southwest China is found to be an important and special area for LPCCG flash activity in China. Not only is it the density center of +/- LPCCG flashes, but the peak current distribution of -LPCCG flashes in this region also shows an evidently different pattern from those in other regions. The diurnal evolution of the -LPCCG/+LPCCG flash frequencies in Southwest China also shows a different pattern from that in other regions.

关键词： climatological characteristics cloud-to-ground lightning flashes with large peak currents Southwestern China

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An improvement of convective precipitation nowcasting through lightning data dynamic nudging in a cloud-resolving scale forecasting system

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ATMOSPHERIC RESEARCH 2020年 242卷 104994-104994页

作者： Wang, Hong chen, Dehui Yin, Jinfang Xu, Daosheng Dai, Guangfeng chen, luwen CMA Key Lab Reg Numer Weather Predict Guangzhou Inst Trop & Marine Meteorol Guangzhou 510080 Peoples R China China Meteorol Adm State Key Lab Severe Weather LaSW Chinese Acad Meteorol Sci Beijing 100081 Peoples R China Natl Meteorol Ctr Numer Weather Predict Ctr Beijing 10081 Peoples R China

A lightning data dynamic nudging (LDN) method was designed to adjust the dynamic field in convective clouds based on the physical relationship between lightning and vertical velocity. Under this framework, vertical velocity data retrieved from the Guangdong-Hongkong-Macau lightning location system were assimilated by a nudging approach using the Global/Regional Assimilation and Prediction System in mesoscale model (GRAPES-Meso). The effect of the assimilation on short-term ( < 6 h) precipitation forecast was evaluated by simulating the squall line event on 7 May and a continuous experiment from May to August 2018. Firstly, a series of sensitivity experiments was carried out to adjust the configuration of the assimilation system based on the squall line event. The results show that LDN expanded the spatial distribution of the positive vertical velocity ( > 1 m s(-1)) at 700 hPa by about 2%, and thus enlarged the spatial distribution of severe rainfall ( > 40 mm h (-1)). It should be noted that LDN did not significantly change the intensity of the updraft (i.e., the maximum vertical velocity) of the squall line relative to the simulation without assimilation. Overall, the equitable threat score (ETS) and fractions skill score (FSS) were increased by 0.04 and 0.13, respectively, and the positive effect lasted for 2-3 h after the data were assimilated. In view of the data assimilation frequency, using two successive nudging procedures with an interval of 12 min had the best effect on the forecast of severe precipitation. For the assimilation of both lightning and radar observations, the asynchronous assimilation of lightning and radar measurements performed slightly better than the synchronous assimilation. LDN improved the accuracy of severe precipitation forecast ( > 40 mm h(-1) and > 20 mm h(-1) for the squall line case and the continuous run, respectively), whereas assimilating radar data improved weak precipitation forecast (1-20 mm h(-1) in the squall line case an

关键词： Lightning data dynamic nudging Lightning location system Short-time forecast Severe precipitation

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Study on the influence of different tire cord structures on tire grounding characteristics

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JOURNAL OF ENGINEERED FIBERS AND FABRICS 2022年 17卷

作者： Zhou, Shuiting chen, luwen Li, Yue Sun, Pengfei Su, Guoyun Meng, Junling Xiamen Univ Technol Sch Mech & Automot Engn Xiamen 361024 Peoples R China

The influence of different tire skeleton structural parameters on tire grounding characteristics was investigated. Using a 225/60R18 100H radial tire as the research object, the experiment and simulation were carried out by changing the diameter of the belt steel wire, the angle of the belt layer, and the number of carcass plies. Using the model parameters obtained from the rubber physical test, the finite element model of the tire was created in Abaqus for static loading simulations, the relevant data such as tire pattern impression and sinkage were analyzed, and the validity of the model was investigated. The influence of skeleton material on tire structure was deduced by determining the amount of stored strain energy of tire. The results showed that the belt angle in the grounding area had the greatest influence on the belt stress and presented a second-order change. However, the number of carcass cord layers and the diameter of the belt steel wire had little effect on the corresponding skeleton stress. The number of carcass layers had the greatest influence on the stored strain energy of the tires. The diameter of the bundled steel wire and the angle of the bundle had little influence.

关键词： Tire skeleton tire grounding characteristics Abaqus stored strain energy

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夏枯草颗粒对乳腺增生症患者疼痛程度及性激素水平的影响

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首都食品与医药 2024年第4期31卷 135-137页

作者：陈露文曾慧雷敏江西省赣州市肿瘤医院江西赣州341000

目的探讨乳腺增生症患者使用夏枯草颗粒治疗的效果.方法将2021年1月-2023年1月赣州市肿瘤医院收治的100例乳腺增生症患者随机分为两组,每组各50例,对照组采用枸橼酸托瑞米芬片治疗,基于此,观察组加用夏枯草颗粒,均治疗2个月.比较两组... 详细信息

目的探讨乳腺增生症患者使用夏枯草颗粒治疗的效果.方法将2021年1月-2023年1月赣州市肿瘤医院收治的100例乳腺增生症患者随机分为两组,每组各50例,对照组采用枸橼酸托瑞米芬片治疗,基于此,观察组加用夏枯草颗粒,均治疗2个月.比较两组治疗效果、疼痛程度、性激素水平及不良反应.结果与对照组治疗总有效率84.00%(42/50)比较,观察组治疗总有效率98.00%(49/50)更高(P<0.05);两组治疗后视觉模拟评分法(VAS)评分均比治疗前低,且观察组比对照组低(P<0.05);治疗后,两组孕酮(P)水平均比治疗前高,且观察组更高,两组睾酮(T)、黄体生成素(LH)、促卵泡成熟素(FSH)、雌二醇(E_(2))水平均比治疗前低,且观察组比对照组低(P<0.05);观察组不良反应发生率4.00%(2/50)与对照组8.00%(4/50)比较,无统计学差异(P>0.05).结论乳腺增生症患者采用夏枯草颗粒治疗效果满意,可有效缓解疼痛,调节性激素水平,且安全性高.

关键词：乳腺增生症夏枯草颗粒疼痛程度性激素

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