番茄在生长过程中易受以病毒病为主的病害侵袭,对其产量和质量造成巨大影响。针对现有番茄植株病害检测方法存在精度低、泛化能力差的问题,构建了一种基于改进YOLOv8-AM算法的检测模型。通过对Plant Village Dataset公共数据集和实地采...番茄在生长过程中易受以病毒病为主的病害侵袭,对其产量和质量造成巨大影响。针对现有番茄植株病害检测方法存在精度低、泛化能力差的问题,构建了一种基于改进YOLOv8-AM算法的检测模型。通过对Plant Village Dataset公共数据集和实地采集的番茄病毒病害检测数据集进行数据增强,构成番茄病毒病害最终的训练数据集和验证数据集。同时,基于YOLOv8模型框架,借鉴残差网络和人眼视觉注意力机制,引入ResBlock+CBAM结构,设计ResCBAM模块,提升模型对关键特征的提取能力。在Plant Village Dataset公共数据集上进行训练与测试,并在番茄病毒病自建数据集上进行试验预测与验证,最终基于Java平台的Spring Boot框架,开发出一种基于YOLOv8-AM的番茄病毒病害检测系统。试验结果表明:在公共数据集上,YOLOv8-AM算法的精确率、召回率分别为92.47%和93.91%,均值平均精度为97.82%,模型的检测速度为31.89 FPS、尺寸为23.83 MB,改进算法在保持检测速度的同时精度均高于现有模型;在自建数据集上,YOLOv8-AM算法的均值平均精度为89.76%,模型泛化能力较强。利用改进的YOLOv8-AM算法能够实现对番茄病毒病害的快速检测,为作物植株的病害识别与防治提供技术支撑。展开更多
针对多端柔性直流电网(multi-terminal direct current grid based on modular multilevel converter,MMC-MTDC)故障诊断存在的人工整定阈值过程复杂、高阻故障不易检测的问题,提出一种基于行波特征的诊断方法。首先,通过分析系统的故...针对多端柔性直流电网(multi-terminal direct current grid based on modular multilevel converter,MMC-MTDC)故障诊断存在的人工整定阈值过程复杂、高阻故障不易检测的问题,提出一种基于行波特征的诊断方法。首先,通过分析系统的故障特征,得出边界元件对高频信号的阻滞作用;其次,利用经验模态分解(empirical mode decomposition,EMD)对功率进行分解,得到本征模态函数(intrinsic mode function,IMF)分量,将其能量值作为故障特征量训练由卷积神经网络(convolutional neural network,CNN)和双向门控循环单元(bidirectional gated recurrent unit,BiGRU)组成的CNN-BiGRU网络;然后,采用开普勒优化算法(Kepler optimization algorithm,KOA)和注意力机制(attention mechanism,AM)对CNN-BiGRU网络进行改进,实现MMC-MTDC的故障诊断;最后,在PSCAD/EMTDC中搭建仿真模型。结果表明,该方法不仅可以实现母线故障和线路故障的检测,还可以在满足保护可靠性和速动性的前提下,解决高阻故障保护易拒动的问题。展开更多
In the field of computer research,the increase of data in result of societal progress has been remarkable,and the management of this data and the analysis of linked businesses have grown in popularity.There are numero...In the field of computer research,the increase of data in result of societal progress has been remarkable,and the management of this data and the analysis of linked businesses have grown in popularity.There are numerous practical uses for the capability to extract key characteristics from secondary property data and utilize these characteristics to forecast home prices.Using regression methods in machine learning to segment the data set,examine the major factors affecting it,and forecast home prices is the most popular method for examining pricing information.It is challenging to generate precise forecasts since many of the regression models currently being utilized in research are unable to efficiently collect data on the distinctive elements that correlate y with a high degree of house price movement.In today’s forecasting studies,ensemble learning is a very prevalent and well-liked study methodology.The regression integration computation of large housing datasets can use a lot of computer resources as well as computation time,and ensemble learning uses more resources and calls for more machine support in integrating diverse models.The Average Model suggested in this paper uses the concept of fusion to produce integrated analysis findings from several models,combining the best benefits of separate models.The Average Model has a strong applicability in the field of regression prediction and significantly increases computational efficiency.The technique is also easier to replicate and very effective in regression investigations.Before using regression processing techniques,this work creates an average of different regression models using the AM(Average Model)algorithm in a novel way.By evaluating essential models with 90%accuracy,this technique significantly increases the accuracy of house price predictions.The experimental results show that the AM algorithm proposed in this paper has lower prediction error than other comparison algorithms,and the prediction accuracy is greatly improved compared with other algorithms,and has a good experimental effect in house price prediction.展开更多
文摘番茄在生长过程中易受以病毒病为主的病害侵袭,对其产量和质量造成巨大影响。针对现有番茄植株病害检测方法存在精度低、泛化能力差的问题,构建了一种基于改进YOLOv8-AM算法的检测模型。通过对Plant Village Dataset公共数据集和实地采集的番茄病毒病害检测数据集进行数据增强,构成番茄病毒病害最终的训练数据集和验证数据集。同时,基于YOLOv8模型框架,借鉴残差网络和人眼视觉注意力机制,引入ResBlock+CBAM结构,设计ResCBAM模块,提升模型对关键特征的提取能力。在Plant Village Dataset公共数据集上进行训练与测试,并在番茄病毒病自建数据集上进行试验预测与验证,最终基于Java平台的Spring Boot框架,开发出一种基于YOLOv8-AM的番茄病毒病害检测系统。试验结果表明:在公共数据集上,YOLOv8-AM算法的精确率、召回率分别为92.47%和93.91%,均值平均精度为97.82%,模型的检测速度为31.89 FPS、尺寸为23.83 MB,改进算法在保持检测速度的同时精度均高于现有模型;在自建数据集上,YOLOv8-AM算法的均值平均精度为89.76%,模型泛化能力较强。利用改进的YOLOv8-AM算法能够实现对番茄病毒病害的快速检测,为作物植株的病害识别与防治提供技术支撑。
文摘由于地铁受电弓—接触线系统受电力列车运行速度限制,采用高空刚性架设接触供电方式.接触网实时参数测量和整定过程中,主要取决精密仪器结构状态与测量参数误差校正.传统的测量仪器采用激光相机与传感器组合方式,其数据传输整定慢、计算复杂融合难度大、受地铁隧道环境影响模型辨识度低等缺点.文中提出一种基于模糊理论的MPC(Model Prediction Control,模型预测控制)算法,在实时测量目标点定位和数据优化精度方面,与PID控制策略比较.AME/simulink试验仿真表明,基于模糊理论的MPC预测算法能提高测量仪器定位点位置预测校正,测量点轨迹协同精度提高15%,减少软件计算数据的作业量20%,提高数据处理精准度±10 mm.
基金This work was supported in part by Sichuan Science and Technology Program(Grant No.2022YFG0174)in part by the Sichuan Gas Turbine Research Institute stability support project of China Aero Engine Group Co.,Ltd(Grant No.GJCZ-0034-19)。
文摘In the field of computer research,the increase of data in result of societal progress has been remarkable,and the management of this data and the analysis of linked businesses have grown in popularity.There are numerous practical uses for the capability to extract key characteristics from secondary property data and utilize these characteristics to forecast home prices.Using regression methods in machine learning to segment the data set,examine the major factors affecting it,and forecast home prices is the most popular method for examining pricing information.It is challenging to generate precise forecasts since many of the regression models currently being utilized in research are unable to efficiently collect data on the distinctive elements that correlate y with a high degree of house price movement.In today’s forecasting studies,ensemble learning is a very prevalent and well-liked study methodology.The regression integration computation of large housing datasets can use a lot of computer resources as well as computation time,and ensemble learning uses more resources and calls for more machine support in integrating diverse models.The Average Model suggested in this paper uses the concept of fusion to produce integrated analysis findings from several models,combining the best benefits of separate models.The Average Model has a strong applicability in the field of regression prediction and significantly increases computational efficiency.The technique is also easier to replicate and very effective in regression investigations.Before using regression processing techniques,this work creates an average of different regression models using the AM(Average Model)algorithm in a novel way.By evaluating essential models with 90%accuracy,this technique significantly increases the accuracy of house price predictions.The experimental results show that the AM algorithm proposed in this paper has lower prediction error than other comparison algorithms,and the prediction accuracy is greatly improved compared with other algorithms,and has a good experimental effect in house price prediction.
