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融合注意力机制的YOLOv8-TS交通标志检测网络

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现代电子技术 2025年第1期48卷 179-186页

作者：黄智渊方遒郭星浩厦门理工学院机械与汽车工程学院福建厦门361024 厦门大学航空航天学院福建厦门361005

道路交通标志识别是自动驾驶、车联网的重要组成部分,为进一步提高交通标志检测的精度和速度,提出一种基于YOLOv8s改进的YOLOv8-TS道路交通标志检测网络。首先,对YOLOv8s进行了整体的轻量化设计,并设计了Conv-G7S和CSP-G7S模块,减少了... 详细信息

道路交通标志识别是自动驾驶、车联网的重要组成部分,为进一步提高交通标志检测的精度和速度,提出一种基于YOLOv8s改进的YOLOv8-TS道路交通标志检测网络。首先,对YOLOv8s进行了整体的轻量化设计,并设计了Conv-G7S和CSP-G7S模块,减少了网络的参数量;其次,设计了CSP-SwinTransformer模块,强化了模型利用窗口内的特征信息进行上下文感知和建模的能力;然后,在颈部网络融合了卷积注意力机制(CBAM),强化了模型对不同通道、空间权重信息的学习;最后,对损失函数进行了改进,提升了边界框回归性能。实验结果表明,在中国道路交通标志TT100K数据集上,精确率(Precision)、平均精度(mAP@0.5)分别提高了6.9%、3.7%,而改进后模型的参数量下降了75.4%,模型的大小仅为5.8 MB,平均精度(mAP@0.5)达到96.5%,检测速度由126.58 f/s提升至136.99 f/s。

关键词：交通标志检测 YOLOv8-TS 轻量化注意力机制 Conv-G7S WIoU

8周运动预适应增强脂肪干细胞治疗心肌梗死大鼠的效果

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中国组织工程研究 2025年第7期29卷 1363-1370页

作者：娄国张敏付常喜江苏经贸职业技术学院江苏省南京市211168 南京旅游职业学院江苏省南京市211100 徐州工程学院体育学院江苏省徐州市221008

背景:干细胞移植是心肌梗死的崭新疗法,然而梗死区域极其恶劣的微环境造成干细胞存活率低下并导致远期疗效甚微。运动预适应是一种通过运动诱导机体产生内源性保护效应的方式,可作为心脏康复预防与治疗的新策略。目的:评估运动预适应是... 详细信息

背景:干细胞移植是心肌梗死的崭新疗法,然而梗死区域极其恶劣的微环境造成干细胞存活率低下并导致远期疗效甚微。运动预适应是一种通过运动诱导机体产生内源性保护效应的方式,可作为心脏康复预防与治疗的新策略。目的:评估运动预适应是否能够增强大鼠心肌梗死后脂肪干细胞移植的心脏保护效应,探讨血管生成在其中的作用机制。方法:6周龄雄性SD大鼠随机分为对照组、造模组、干细胞组以及干细胞运动组。利用冠状动脉闭塞术制作急性心肌梗死模型,对照组同期行假手术;干细胞运动组于造模前进行8周有氧运动,造模后30 min进行脂肪干细胞移植;干细胞组仅进行脂肪干细胞移植。干细胞移植后1 d和7 d,利用免疫印迹法测定心肌总Akt(t-Akt)、磷酸化Akt(p-Akt)、血管内皮生长因子(VEGF)、总内皮型一氧化氮合酶(t-eNOS)和磷酸化内皮型一氧化氮合酶(p-eNOS)蛋白表达量,计算p-Akt/t-Akt和p-eNOS/t-eNOS比值;4周后利用彩色多普勒超声诊断系统检测心脏结构与功能以及心肌血流量,TTC染色法检测心肌梗死面积,Masson染色法检测心肌间质胶原沉积,免疫荧光染色法测定心肌毛细血管密度,TUNEL染色法评估心肌细胞凋亡。结果与结论:(1)干细胞移植后4周:与对照组比较,造模组左心室缩短分数、左心室射血分数、心肌毛细血管密度和心肌血流量下降(P0.05);与造模组比较,干细胞组上述指标均无显著性变化(P>0.05),干细胞运动组磷酸化p-Akt蛋白表达量以及p-Akt/t-Akt比值上调(P0.05),干细胞运动组p-Akt、VEGF、p-eNOS蛋白表达量以及p-Akt/t-Akt、p-eNOS/t-eNOS比值升高(P<0.05)。结果表明:运动预适应可增强脂肪干细胞对心肌梗死大鼠心脏重塑的治疗效果,其机制与促进心肌血管生成并增加血流灌注有关。

关键词：干细胞脂肪干细胞运动预适应心肌梗死血管生成心脏重塑血流灌注

Spraying Arginine at 5 Days before Harvest Delays Postharvest Broccoli Senescence via Nutrient Accumulation

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食品科学 2025年第1期46卷 131-141页

作者： SUN Yupeng CHEN Ying SHANG Qingwen guo Yanyin ZHANG Yuxiao WANG Yunqiao XUE Qingyue College of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255049China Zichuan District Agricultural and Rural Affairs Service Center Zibo 255049China

To determine the effects of preharvest arginine spraying on the nutritional level of broccoli and the mechanism of action of arginine in improving the storage quality of broccoli,arginine spraying(5 mmol/L)was conducted at 0,1,3,and 5 days before *** appearance,respiration rate,mass-loss rate,electrolyte leakage,glucosinolate,ascorbic acid,total phenol,total flavonoid,total sugar and sucrose contents,and sucrose phosphate synthase(SPS),invertase(INV),sucrose synthase synthesis(SSS)and cleavage(SSC)activities of broccoli samples were observed after 0,2,4,6,8,and 10 days of *** results showed that spraying arginine at 5 days preharvest(5-ARG)helped to inhibit broccoli respiration during storage,delay electrolyte leakage,and maintain broccoli ***,during the growth stage,total sugar accumulation was higher in the 5-ARG *** addition,during the storage period,sucrose synthesis was accelerated,while sucrose cleavage was inhibited,resulting in more sucrose retention in postharvest *** conclusion,5-ARG resulted in the accumulation of more nutrients during the growth process and effectively delayed the quality decline during storage,thereby prolonging the shelf life of ***,this study provides a theoretical basis for improving postharvest storage characteristics of broccoli through preharvest treatments.

关键词： arginine broccoli preharvest spraying nutrient accumulation storage quality postharvest senescence

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二维Janus LuClI的铁谷特性研究

原子与分子物理学报 2025年第2期42卷 159-168页

作者：朱靖欣郭三栋西安邮电大学电子工程学院西安710121

铁谷材料由于其固有的铁磁性质,可以产生自发谷极化,从而实现谷自由度的操纵.不同的谷极化状态为铁谷材料在信息传递领域的应用提供了可能性.在本文的工作中,采用了可靠的第一性原理计算方法,证明了Janus单层LuClI的动力学、力学和热力... 详细信息

铁谷材料由于其固有的铁磁性质,可以产生自发谷极化,从而实现谷自由度的操纵.不同的谷极化状态为铁谷材料在信息传递领域的应用提供了可能性.在本文的工作中,采用了可靠的第一性原理计算方法,证明了Janus单层LuClI的动力学、力学和热力学稳定性.发现Janus单层LuClI是一种有潜力的铁谷材料,它有着50.927 meV的谷劈裂.当Lu原子磁矩方向(平面外)发生颠倒时,可以实现谷极化翻转.还计算了Janus单层LuClI在布里渊区中的Berry曲率分布,主要集中在-K和K谷,可以实现反常谷霍尔效应.当电子关联强度比较小时,Janus单层LuClI的易磁化轴将指向面内,从而失去自发谷极化.尽管如此,利用应变调控可以使磁化方向从面内转向面外,从而产生谷极化.此外,Janus单层LuClI同时具有面内和面外压电响应,计算得到的面内压电应变系数d11大于大部分已有二维材料的计算值,而面外压电系数d31非常小.这为通过压电效应调控谷载流子提供了可能性.

关键词：铁谷材料压电第一性原理计算

Tracking Control in Presence of Obstacles and Uncertainties for Bioinspired Spherical Underwater Robots

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Journal of Bionic Engineering 2023年第1期20卷 323-337页

作者： Chunying Li Shuxiang guo Jian guo Graduate School of Engineering Kagawa UniversityTakamatsuKagawa761-0396Japan Key Laboratory of Convergence Medical Engineering System and Healthcare Technology the Ministry of Industry and Information TechnologySchool of Life Science and TechnologyBeijing Institute of TechnologyBeijing100081China Tianjin Key Laboratory for Control Theory and Applications in Complicated Systems and Intelligent Robot Laboratory Tianjin University of TechnologyBinshui Xidao Extension 391Tianjin300384China

During marine missions,AUVs are susceptible to external disturbances,such as obstacles,ocean currents,etc.,which can easily cause mission failure or *** this paper,considering the strong nonlinearities,external disturbances and obstacles,the kinematic and dynamic model of bioinspired Spherical Underwater Robot(SUR)was ***,the waypoints-based trajectory tracking with obstacles and uncertainties was proposed for SUR to guarantee its safety and ***,the Lyapunov theory was adopted to verify the stability and the Slide Mode Control(SMC)method is used to verify the robustness of the control *** addition,a series of simulations were conducted to evaluate the effectiveness of proposed control *** tests,including path-following,static and moving obstacle avoidance were performed which verified the feasibility,robustness and effectiveness of the designed control ***,a series of experiments in real environment were performed to verify the performance of the control *** simulation and experimental results of the study supplied clues to the improvement of the path following capability and multi-obstacle avoidance of AUVs.

关键词： Path following Obstacle avoidance Bioinspired.Spherical underwater robot(SUR) Lyapunov theory

Electro-lubrication in Janus transition metal dichalcogenide bilayers

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Friction 2022年第11期10卷 1851-1858页

作者： Hao LI Yufeng guo Wanlin guo State Key Laboratory of Mechanics and Control of Mechanical Structures MOE Key Laboratory for Intelligent Nano Materials and DevicesCollege of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

Lubrication induced by a vertical electric field or bias voltage is typically not applicable to twodimensional(2D)van der Waals(vdW)*** performing extensive first-principles calculations,we reveal that the interlayer friction and shear resistance of Janus transition metal dichalcogenide(TMD)MoXY(X/Y=S,Se,or Te,and X≠Y)bilayers under a constant normal force mode can be reduced by applying vertical electric *** maximum interlayer sliding energy barriers between AA and AB stacking of bilayers MoSTe,MoSeTe,and MoSSe decrease as the positive electric field increases because of the more significant counteracting effect from the electric field energy and the more significant enhancement in interlayer charge transfer in AA ***,the presence of negative electric fields decreases the interlayer friction of bilayer MoSTe,because the electronegativity difference between Te and S atoms reduces the interfacial atom charge differences between AA and AB *** results reveal an electro-lubrication mechanism for the heterogeneous interfaces of 2D Janus TMDs.

关键词： Janus transition metal dichalcogenide(TMD) electro-lubrication electric field tuning first-principles calculations

Ultralow friction of ion-containing water nanodroplets

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Nano Research 2023年第1期16卷 1792-1797页

作者： Jie Tan Yufeng guo Wanlin guo State Key Laboratory of Mechanics and Control of Mechanical Structures MOE Key Laboratory for Intelligent Nano Materials and DevicesCollege of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

We reveal the ultralow friction or superlubricity of water nanodroplets containing cations and anions on graphene substrates at high ion concentration by molecular dynamics *** the ion concentration is higher than 7 wt.%and the nanodroplet diameter is larger than 10 nm,the friction coefficients of water nanodroplets are lower than 10−2,and can decrease to the order of 10−3 with increasing the ion concentration *** a certain ion concentration,the optimal nanodroplet diameter of 17–20 nm exists at which the friction coefficient is the *** ultralow friction behaviors of water nanodroplets containing cations and anions are mainly attributed to the opposite variation trends between the interfacial adhesion energy and surface energy of water nanodroplet with ion concentration,and the interfacial hydrophobicity sustained by high ion *** results unveil the essential role of ions in achieving the superlubricity of water nanodroplets.

关键词： water nanodroplet ion ultralow friction molecular dynamics

Emerging direct current triboelectric nanogenerator for high-entropy mechanical energy harvesting

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Science China(Technological Sciences) 2024年第5期67卷 1297-1316页

作者： CHEN Jie guo RuiLong guo HengYu College of Physics and Electronic Engineering Chongqing Normal UniversityChongqing 401331China Department of Applied Physics Chongqing UniversityChongqing 401331China

In the era of the Internet of Things(IoT),the provision of sustainable power to distributed,mobile,and low-power-consumption electronic devices is a critical *** overcome this challenge,the triboelectric nanogenerator(TENG),a highly efficient high-entropy mechanical energy harvesting device,was developed in *** device enables the direct conversion of irregular and low-frequency mechanical energy into pulsed alternating current(AC)***,the incompatibility of most electronic devices with AC signals necessitates rectifier circuits or generators that deliver direct current(DC)*** recent years,DC-TENGs have undergone extensive development,achieving significant milestones in various application fields while also facing crucial challenges that require *** this review,three categories of DC-TENG devices with distinct operating mechanisms are comprehensively explored:multiphase coupling,mechanical rectification,and air *** typical structures and working mechanisms are thoroughly discussed,and specific output performance limitations,along with corresponding optimization strategies,are ***,the applications of DC-TENGs in various scenarios are ***,the challenges faced by DC-TENGs and potential solutions are analyzed to guide further advancements in this technology.

关键词： TENG direct current working mechanisms output performance limitations optimization strategies

Chiral metal phosphonates: assembly, structures and functions

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Science China Chemistry 2020年第5期63卷 619-636页

作者： guo-guo Weng Li-Min Zheng State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringCollaborative Innovation Centre of Advanced MicrostructuresNanjing UniversityNanjing 210023China

As an important class of inorganic-organic hybrid materials, metal phosphonates can exhibit versatile structures, interesting functions and high water and thermal stabilities. Despite a large number of metal phosphonates reported in the past two decades,the development of chiral metal phosphonates is still in its infancy. This review summarizes the current status in this topical field including the synthetic strategies, the crystal structures of chiral metal phosphonates reported thus far, and their physical and chemical properties. Future challenges in this promising field are also discussed.

关键词： chiral metal phosphonate structure property