Aiming at the problem of imbalance between detection accuracy and algorithm model lightweight in UAV aerial image target detection algorithm,a lightweight multi-category abnormal behavior detection algorithm based on ...Aiming at the problem of imbalance between detection accuracy and algorithm model lightweight in UAV aerial image target detection algorithm,a lightweight multi-category abnormal behavior detection algorithm based on improved YOLOv11n is designed.By integrating multi-head grouped self-attention mechanism and Partial-Conv,a two-way feature grouping fusion module(DFPF)was designed,which carried out effective channel segmentation and fusion strategies to reduce redundant calculations andmemory access.C3K2 module was improved,and then unstructured pruning and feature distillation technologywere used.The algorithmmodel is lightweight,and the feature extraction ability for airborne visual abnormal behavior targets is strengthened,and the computational efficiency of the model is improved.Finally,we test the generalization of the baseline model and the improved model on the VisDrone2019 dataset.The results show that com-pared with the baseline model,the detection accuracy of the final improved model on the airborne visual abnormal behavior dataset is improved from 90.2% to 94.8%,and the model parameters are reduced by 50.9% to meet the detection requirements of high efficiency and high precision.The detection accuracy of the improved model on the Vis-Drone2019 public dataset is 1.3% higher than that of the baseline model,indicating the effectiveness of the improved method in this paper.展开更多
针对传统产品保障领域中故障诊断过度依赖维修人员经验、诊断准确率低、实时性不足等问题,本文提出一种基于分段退化理论修正权重的AdaBoost-CART算法,以实现产品故障的智能诊断。该方法通过分类与回归树(Classification and Regression...针对传统产品保障领域中故障诊断过度依赖维修人员经验、诊断准确率低、实时性不足等问题,本文提出一种基于分段退化理论修正权重的AdaBoost-CART算法,以实现产品故障的智能诊断。该方法通过分类与回归树(Classification and Regression Trees,CART)算法建立故障弱分类器,将AdaBoost和分段退化理论相结合,构建用于修正样本权重的动态权重迭代机制,同时强化对错分样本的特征提取,形成具有强泛化能力的AdaBoost-CART分类模型。在产品发动机故障数据集上的验证结果表明,优化后的AdaBoost-CART算法准确率达到94.6%,相比优化前产品故障诊断的准确率提升了8.6个百分点。本文所提算法为产品保障维修提供了合理的辅助决策依据,提升了产品保障决策效率和产品工作可靠性。展开更多
In order to solve the problems of weak prediction stability and generalization ability of a neural network algorithm model in the yarn quality prediction research for small samples,a prediction model based on an AdaBo...In order to solve the problems of weak prediction stability and generalization ability of a neural network algorithm model in the yarn quality prediction research for small samples,a prediction model based on an AdaBoost algorithm(AdaBoost model) was established.A prediction model based on a linear regression algorithm(LR model) and a prediction model based on a multi-layer perceptron neural network algorithm(MLP model) were established for comparison.The prediction experiments of the yarn evenness and the yarn strength were implemented.Determination coefficients and prediction errors were used to evaluate the prediction accuracy of these models,and the K-fold cross validation was used to evaluate the generalization ability of these models.In the prediction experiments,the determination coefficient of the yarn evenness prediction result of the AdaBoost model is 76% and 87% higher than that of the LR model and the MLP model,respectively.The determination coefficient of the yarn strength prediction result of the AdaBoost model is slightly higher than that of the other two models.Considering that the yarn evenness dataset has a weaker linear relationship with the cotton dataset than that of the yarn strength dataset in this paper,the AdaBoost model has the best adaptability for the nonlinear dataset among the three models.In addition,the AdaBoost model shows generally better results in the cross-validation experiments and the series of prediction experiments at eight different training set sample sizes.It is proved that the AdaBoost model not only has good prediction accuracy but also has good prediction stability and generalization ability for small samples.展开更多
硬岩隧道掘进机(hard rock tunnel boring machine,TBM)在隧道掘进过程中施工时,由于面临着复杂地质状况,多依赖人工经验进行施工,在遇到复杂地质状况时,很难进行有效调整,容易出现卡死等重大事故,造成巨大的经济损失,延误施工进度。在...硬岩隧道掘进机(hard rock tunnel boring machine,TBM)在隧道掘进过程中施工时,由于面临着复杂地质状况,多依赖人工经验进行施工,在遇到复杂地质状况时,很难进行有效调整,容易出现卡死等重大事故,造成巨大的经济损失,延误施工进度。在面对各种不同地质情况时,隧道掘进通常都是依赖于人工经验来对TBM进行控制,在遇到复杂的地质状况时,很难进行及时有效的调整,很容易出现TBM卡机等严重事故,造成巨大的经济损失,并耽误工期。为解决TBM掘进过程中人为对前方围岩等级做出判断而易出现的上述问题,提出了一种基于机器学习的围岩等级实时识别预测方法,即通过AdaBoost集成算法对CART回归树模型进行弱分类器优化构建AdaBoost-CART的围岩等级预测模型,并将该模型应用于广花城际项目工程,对TBM掘进前方的围岩等级进行预测。结果表明:相较于其他预测模型,AdaBoost-CART模型预测正确率提升最大有8.58%,表明在给定总推进力、刀盘转速、推进速度及刀盘扭矩4个输入变量,围岩等级1个输出变量的条件下,AdaBoost-CART模型能够很好地预测围岩等级。此外,经数据预处理后的围岩等级的预测正确率相较预处理前提升了7.73%,很好地证明了预测前对数据集进行数据预处理的重要性。这些认识与成果,验证了AdaBoost-CART预测模型在围岩等级预测中具有更好地预测能力,以期为同类型的TBM掘进前方围岩等级预测分类提供参考。展开更多
针对传统油中溶解气体分析(dissolved gas analysis,DGA)在油浸变压器故障诊断过程中不能够有效地利用故障信息,以及变压器故障样本类型不平衡致使模型诊断结果较差的情况,提出了基于数据扩充和故障特征优化的SCNGO-SVM-AdaBoost变压器...针对传统油中溶解气体分析(dissolved gas analysis,DGA)在油浸变压器故障诊断过程中不能够有效地利用故障信息,以及变压器故障样本类型不平衡致使模型诊断结果较差的情况,提出了基于数据扩充和故障特征优化的SCNGO-SVM-AdaBoost变压器故障诊断技术。首先,针对不平衡样本数据集利用安全级别合成少数过采样技术(safelevel synthetic minority over-sampling technique,Safe-Level SMOTE)对原始的变压器故障样本集进行了数据扩充,然后利用核主成分分析(kernel principal component analysis,K-PCA)算法对比值化后的油色谱数据进行故障特征优化提取。其次在北方苍鹰优化算法(northern goshawk optimization,NGO)中融合了正余弦和折射反向学习策略,利用测试函数验证该算法的稳定性和利用SCNGO优化算法提高其寻优能力。最后通过实际的对未扩充样本诊断和其他方法诊断进行对比分析,结果证明该方法能够有效地提高变压器故障诊断的性能。展开更多
基金supported by y the Applied Research Advancement Project in Engineering University of PAP(WYY202304)Research and Innovation Team Project in Engineering University of PAP(KYTD202306)Funding for postgraduate education and teaching.
摘要Aiming at the problem of imbalance between detection accuracy and algorithm model lightweight in UAV aerial image target detection algorithm,a lightweight multi-category abnormal behavior detection algorithm based on improved YOLOv11n is designed.By integrating multi-head grouped self-attention mechanism and Partial-Conv,a two-way feature grouping fusion module(DFPF)was designed,which carried out effective channel segmentation and fusion strategies to reduce redundant calculations andmemory access.C3K2 module was improved,and then unstructured pruning and feature distillation technologywere used.The algorithmmodel is lightweight,and the feature extraction ability for airborne visual abnormal behavior targets is strengthened,and the computational efficiency of the model is improved.Finally,we test the generalization of the baseline model and the improved model on the VisDrone2019 dataset.The results show that com-pared with the baseline model,the detection accuracy of the final improved model on the airborne visual abnormal behavior dataset is improved from 90.2% to 94.8%,and the model parameters are reduced by 50.9% to meet the detection requirements of high efficiency and high precision.The detection accuracy of the improved model on the Vis-Drone2019 public dataset is 1.3% higher than that of the baseline model,indicating the effectiveness of the improved method in this paper.
摘要针对传统产品保障领域中故障诊断过度依赖维修人员经验、诊断准确率低、实时性不足等问题,本文提出一种基于分段退化理论修正权重的AdaBoost-CART算法,以实现产品故障的智能诊断。该方法通过分类与回归树(Classification and Regression Trees,CART)算法建立故障弱分类器,将AdaBoost和分段退化理论相结合,构建用于修正样本权重的动态权重迭代机制,同时强化对错分样本的特征提取,形成具有强泛化能力的AdaBoost-CART分类模型。在产品发动机故障数据集上的验证结果表明,优化后的AdaBoost-CART算法准确率达到94.6%,相比优化前产品故障诊断的准确率提升了8.6个百分点。本文所提算法为产品保障维修提供了合理的辅助决策依据,提升了产品保障决策效率和产品工作可靠性。
摘要In order to solve the problems of weak prediction stability and generalization ability of a neural network algorithm model in the yarn quality prediction research for small samples,a prediction model based on an AdaBoost algorithm(AdaBoost model) was established.A prediction model based on a linear regression algorithm(LR model) and a prediction model based on a multi-layer perceptron neural network algorithm(MLP model) were established for comparison.The prediction experiments of the yarn evenness and the yarn strength were implemented.Determination coefficients and prediction errors were used to evaluate the prediction accuracy of these models,and the K-fold cross validation was used to evaluate the generalization ability of these models.In the prediction experiments,the determination coefficient of the yarn evenness prediction result of the AdaBoost model is 76% and 87% higher than that of the LR model and the MLP model,respectively.The determination coefficient of the yarn strength prediction result of the AdaBoost model is slightly higher than that of the other two models.Considering that the yarn evenness dataset has a weaker linear relationship with the cotton dataset than that of the yarn strength dataset in this paper,the AdaBoost model has the best adaptability for the nonlinear dataset among the three models.In addition,the AdaBoost model shows generally better results in the cross-validation experiments and the series of prediction experiments at eight different training set sample sizes.It is proved that the AdaBoost model not only has good prediction accuracy but also has good prediction stability and generalization ability for small samples.
摘要硬岩隧道掘进机(hard rock tunnel boring machine,TBM)在隧道掘进过程中施工时,由于面临着复杂地质状况,多依赖人工经验进行施工,在遇到复杂地质状况时,很难进行有效调整,容易出现卡死等重大事故,造成巨大的经济损失,延误施工进度。在面对各种不同地质情况时,隧道掘进通常都是依赖于人工经验来对TBM进行控制,在遇到复杂的地质状况时,很难进行及时有效的调整,很容易出现TBM卡机等严重事故,造成巨大的经济损失,并耽误工期。为解决TBM掘进过程中人为对前方围岩等级做出判断而易出现的上述问题,提出了一种基于机器学习的围岩等级实时识别预测方法,即通过AdaBoost集成算法对CART回归树模型进行弱分类器优化构建AdaBoost-CART的围岩等级预测模型,并将该模型应用于广花城际项目工程,对TBM掘进前方的围岩等级进行预测。结果表明:相较于其他预测模型,AdaBoost-CART模型预测正确率提升最大有8.58%,表明在给定总推进力、刀盘转速、推进速度及刀盘扭矩4个输入变量,围岩等级1个输出变量的条件下,AdaBoost-CART模型能够很好地预测围岩等级。此外,经数据预处理后的围岩等级的预测正确率相较预处理前提升了7.73%,很好地证明了预测前对数据集进行数据预处理的重要性。这些认识与成果,验证了AdaBoost-CART预测模型在围岩等级预测中具有更好地预测能力,以期为同类型的TBM掘进前方围岩等级预测分类提供参考。