In order to reduce the error judgment of outliers in vehicle temperature prediction and improve the accuracy of single-station processor prediction data,a Kalman filter multi-information fusion algorithm based on opti...In order to reduce the error judgment of outliers in vehicle temperature prediction and improve the accuracy of single-station processor prediction data,a Kalman filter multi-information fusion algorithm based on optimized P-Huber weight function was proposed.The algorithm took Kalman filter(KF)as the whole frame,and established the decision threshold based on the confidence level of Chi-square distribution.At the same time,the abnormal error judgment value was constructed by Mahalanobis distance function,and the three segments of Huber weight function were formed.It could improve the accuracy of the interval judgment of outliers,and give a reasonable weight,so as to improve the tracking accuracy of the algorithm.The data values of four important locations in the vehicle obtained after optimized filtering were processed by information fusion.According to theoretical analysis,compared with Kalman filtering algorithm,the proposed algorithm could accurately track the actual temperature in the case of abnormal error,and multi-station data fusion processing could improve the overall fault tolerance of the system.The results showed that the proposed algorithm effectively reduced the interference of abnormal errors on filtering,and the synthetic value of fusion processing was more stable and critical.展开更多
为探究设施葡萄环境特征与光合速率间的相关性,实现多环境特征耦合下的设施葡萄光合速率精准预测,该研究提出一种基于灰狼算法优化BP的设施葡萄光合速率预测模型(grey wolf optimizer-back propagation,GWO-BP)。首先采集2024年6—9月...为探究设施葡萄环境特征与光合速率间的相关性,实现多环境特征耦合下的设施葡萄光合速率精准预测,该研究提出一种基于灰狼算法优化BP的设施葡萄光合速率预测模型(grey wolf optimizer-back propagation,GWO-BP)。首先采集2024年6—9月妮娜皇后葡萄光合作用数据,然后利用随机森林基尼重要性和最大信息系数筛选出影响光合速率的二氧化碳浓度、空气温度、空气湿度和光合有效辐射关键特征,构建结构为4-12-1的BP模型,使用泽维尔均匀初始化和零初始化算法分别对BP模型的权值和阈值进行初始化,并引入自适应矩估计(adaptive moment estimation,ADAM)算法动态调整学习率,最后通过灰狼算法(grey wolf optimizer,GWO)优化其初始权值和阈值。试验对比分析BP、支持向量回归(support vector regression,SVR)、随机森林(random forest,RF)、极限学习机(extreme learning machine,ELM)4种模型,确定效果最佳的基础模型,然后对比分析GWO-BP模型与基础模型。结果表明BP模型为最佳基础模型,在验证集和测试集的决定系数(R2)分别为0.832和0.834,性能优于其他3种模型;而GWO-BP模型相较于BP模型,其验证集R2提升至0.920,均方根误差下降31.2%,平均绝对误差下降25.1%;GWO-BP模型相较于BP模型,其测试集R2提升至0.918,均方根误差下降29.8%,平均绝对误差下降22.5%,Huber损失函数由0.01降低到0.006以下,有效避免BP模型易陷入局部最优的问题,灰狼算法提升BP模型的全局搜索能力和收敛稳定性,使GWO-BP模型在极端值区间的预测性能更优。该模型为准确捕捉设施葡萄光合速率与多环境特征的耦合关系,实现设施葡萄光合速率精准预测提供可靠的技术手段。展开更多
Seismic inversion is a highly ill-posed problem,due to many factors such as the limited seismic frequency bandwidth and inappropriate forward modeling.To obtain a unique solution,some smoothing constraints,e.g.,the Ti...Seismic inversion is a highly ill-posed problem,due to many factors such as the limited seismic frequency bandwidth and inappropriate forward modeling.To obtain a unique solution,some smoothing constraints,e.g.,the Tikhonov regularization are usually applied.The Tikhonov method can maintain a global smooth solution,but cause a fuzzy structure edge.In this paper we use Huber-Markov random-field edge protection method in the procedure of inverting three parameters,P-velocity,S-velocity and density.The method can avoid blurring the structure edge and resist noise.For the parameter to be inverted,the Huber-Markov random-field constructs a neighborhood system,which further acts as the vertical and lateral constraints.We use a quadratic Huber edge penalty function within the layer to suppress noise and a linear one on the edges to avoid a fuzzy result.The effectiveness of our method is proved by inverting the synthetic data without and with noises.The relationship between the adopted constraints and the inversion results is analyzed as well.展开更多
基金supported by Natural Science Foundation of Gansu Province(No.20JR5RA407).
摘要In order to reduce the error judgment of outliers in vehicle temperature prediction and improve the accuracy of single-station processor prediction data,a Kalman filter multi-information fusion algorithm based on optimized P-Huber weight function was proposed.The algorithm took Kalman filter(KF)as the whole frame,and established the decision threshold based on the confidence level of Chi-square distribution.At the same time,the abnormal error judgment value was constructed by Mahalanobis distance function,and the three segments of Huber weight function were formed.It could improve the accuracy of the interval judgment of outliers,and give a reasonable weight,so as to improve the tracking accuracy of the algorithm.The data values of four important locations in the vehicle obtained after optimized filtering were processed by information fusion.According to theoretical analysis,compared with Kalman filtering algorithm,the proposed algorithm could accurately track the actual temperature in the case of abnormal error,and multi-station data fusion processing could improve the overall fault tolerance of the system.The results showed that the proposed algorithm effectively reduced the interference of abnormal errors on filtering,and the synthetic value of fusion processing was more stable and critical.
摘要为了抑制采样点中粗差对数字高程模型(digital elevation model,DEM)建模的影响,以较高精度的多面函数(multi-quadric,MQ)为基函数,由改进Huber损失函数和权重惩罚项组成目标函数,发展了MQ抗差插值算法(MQ-H)。通过优化MQ-H目标函数,采样点权重计算最终转换为方程组求解。以数学曲面为研究对象,将MQ-H计算结果与传统MQ及最小绝对偏差MQ(MQ-L)进行比较,结果表明:当采样误差服从正态分布时,MQ-H计算精度与传统MQ相当,而远高于MQ-L;当采样误差服从拉普拉斯分布时,MQ-H计算精度略高于MQ-L及传统MQ;当采样点被粗差污染时,MQ-H计算精度远高于传统MQ及MQ-L。在实例分析中,以无人遥测飞艇立体像对获取的地面离散高程点为基础数据,基于MQ-H构建测区DEM,并将计算结果与传统插值算法,如反距离加权(inverse distance weighting,IDW)、普通克里金(ordinary Kriging,OK)和专业DEM插值软件ANUDEM(Australian National University DEM)进行比较,结果表明,传统插值方法在不同程度上受采样点中异常值或偶然误差影响,而MQ-H受异常值影响较小,且能准确捕捉到地形细节信息。
摘要为探究设施葡萄环境特征与光合速率间的相关性,实现多环境特征耦合下的设施葡萄光合速率精准预测,该研究提出一种基于灰狼算法优化BP的设施葡萄光合速率预测模型(grey wolf optimizer-back propagation,GWO-BP)。首先采集2024年6—9月妮娜皇后葡萄光合作用数据,然后利用随机森林基尼重要性和最大信息系数筛选出影响光合速率的二氧化碳浓度、空气温度、空气湿度和光合有效辐射关键特征,构建结构为4-12-1的BP模型,使用泽维尔均匀初始化和零初始化算法分别对BP模型的权值和阈值进行初始化,并引入自适应矩估计(adaptive moment estimation,ADAM)算法动态调整学习率,最后通过灰狼算法(grey wolf optimizer,GWO)优化其初始权值和阈值。试验对比分析BP、支持向量回归(support vector regression,SVR)、随机森林(random forest,RF)、极限学习机(extreme learning machine,ELM)4种模型,确定效果最佳的基础模型,然后对比分析GWO-BP模型与基础模型。结果表明BP模型为最佳基础模型,在验证集和测试集的决定系数(R2)分别为0.832和0.834,性能优于其他3种模型;而GWO-BP模型相较于BP模型,其验证集R2提升至0.920,均方根误差下降31.2%,平均绝对误差下降25.1%;GWO-BP模型相较于BP模型,其测试集R2提升至0.918,均方根误差下降29.8%,平均绝对误差下降22.5%,Huber损失函数由0.01降低到0.006以下,有效避免BP模型易陷入局部最优的问题,灰狼算法提升BP模型的全局搜索能力和收敛稳定性,使GWO-BP模型在极端值区间的预测性能更优。该模型为准确捕捉设施葡萄光合速率与多环境特征的耦合关系,实现设施葡萄光合速率精准预测提供可靠的技术手段。
基金supported by the National Basic Research Program of China(973 Program)(No.2013CB228603)National Science and Technology major projects(No.2011ZX05024 and 2011ZX05010)the National Natural Science Foundation of China(No.41174119)
摘要Seismic inversion is a highly ill-posed problem,due to many factors such as the limited seismic frequency bandwidth and inappropriate forward modeling.To obtain a unique solution,some smoothing constraints,e.g.,the Tikhonov regularization are usually applied.The Tikhonov method can maintain a global smooth solution,but cause a fuzzy structure edge.In this paper we use Huber-Markov random-field edge protection method in the procedure of inverting three parameters,P-velocity,S-velocity and density.The method can avoid blurring the structure edge and resist noise.For the parameter to be inverted,the Huber-Markov random-field constructs a neighborhood system,which further acts as the vertical and lateral constraints.We use a quadratic Huber edge penalty function within the layer to suppress noise and a linear one on the edges to avoid a fuzzy result.The effectiveness of our method is proved by inverting the synthetic data without and with noises.The relationship between the adopted constraints and the inversion results is analyzed as well.