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基于CSA-PLS算法的养殖水体水质快速高光谱预测反演模型研究

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海洋与湖沼 2024年第2期55卷 375-385页

作者：马启良刘梅祁亨年杨小明原居林湖州师范学院浙江省现代农业资源智慧管理与应用研究重点实验室浙江湖州313000 湖州师范学院信息工程学院浙江湖州313000 浙江省淡水水产研究所浙江湖州313001

养殖水体水质的优劣直接影响养殖对象的成长,准确、快速、全面地掌控养殖水环境的水质参数变化情况具有重要意义。传统的水质指标监测方法都通过人工采样的方式,不仅耗费时间长,且只能体现局部水体情况。针对这些问题,提出了一种乌鸦搜... 详细信息

养殖水体水质的优劣直接影响养殖对象的成长,准确、快速、全面地掌控养殖水环境的水质参数变化情况具有重要意义。传统的水质指标监测方法都通过人工采样的方式,不仅耗费时间长,且只能体现局部水体情况。针对这些问题,提出了一种乌鸦搜索算法(CSA)结合偏最小二乘回归(PLSR)的高光谱特征波段筛选方法,快速构建回归模型,实现光谱数据的精准预测反演。以连片的养殖小区为研究对象,采集养殖水体样本并拍摄同时期的高光谱影像数据。首先对提取的采样点光谱数据利用多种数据变换方法分别预处理;其次利用这些数据,对水质指标总氮(TN)、氨氮(NH_(4)^(+)-N)、总磷(TP)和化学需氧量(COD)分别构建全波段的SVR和AdaBoost回归模型,同时与提出的CSA-PLS自动筛选波段方法和传统的连续投影算法(SPA)筛选波段后构建的模型进行比较分析;最后根据决定系数(R^(2))和均方根误差(REMS)选出适合各水质指标的最优模型。从实验结果可以看出,所提波段筛选方法的AdaBoost模型预测结果优于SVR和传统SPA方法提取特征波段后构建的模型,与全波段最优模型相比,在评价指标R^(2)和RMSE上TN提升了18.32%和10.73%;NH_(4)^(+)-N提升了17.42%和11.19%;COD提升了2.15%和2.54%。结果表明,基于CSA-PLS算法的光谱波段自动筛选方法结合AdaBoost构建的预测反演模型是有效、可行的,具有较高的精准度,为实现养殖水环境实时准确的预警调控提供了一种新的数据预测模型。

关键词：高光谱数据水质预测乌鸦搜索算法养殖水环境集成学习

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具有稚虫迁徙机制的S型自适应混沌蜉蝣算法

化工自动化及仪表 2024年第2期51卷 262-273页

作者：张恒齐钱谦昆明理工大学信息工程与自动化学院昆明理工大学云南省计算机技术应用重点实验室

针对蜉蝣优化算法(MA)全局搜索能力较弱,对子代优秀个体有效信息利用不够充分的缺点,以及在计算中后期易陷入局部收敛,进而影响优化效果的问题,提出一种具有稚虫迁徙机制的S型自适应混沌蜉蝣优化算法(S-AMA)。S-AMA算法首先采用Logisti... 详细信息

针对蜉蝣优化算法(MA)全局搜索能力较弱,对子代优秀个体有效信息利用不够充分的缺点,以及在计算中后期易陷入局部收敛,进而影响优化效果的问题,提出一种具有稚虫迁徙机制的S型自适应混沌蜉蝣优化算法(S-AMA)。S-AMA算法首先采用Logistic混沌映射产生蜉蝣种群,增加算法初期种群的多样性;随后,将蜉蝣生命周期进行数学建模,并引入S型生命系数替换原有的重力惯性系数,动态调整算法探索能力和开发能力间的平衡性;最后,根据蜉蝣在缺氧环境下的种群活动,引入稚虫迁徙机制强化子代优秀个体摆脱局部最优的能力,进而更加充分地搜索最优解附近的区域,以增强算法的收敛精度。实验部分将S-AMA应用于标准函数测试集,并分别进行优化对比实验、Wilcoxon秩和检验。结果表明:与对比算法相比,S-AMA算法具有更好的寻优能力、收敛速度及鲁棒性。

关键词： S型自适应混沌蜉蝣优化算法(S-AMA) 稚虫迁徙机制混沌映射 S型生命系数莱维飞行

Chip formation dependence of machining velocities in nano-scale by molecular dynamics simulations

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Science China(Technological Sciences) 2014年第12期57卷 2426-2433页

作者： SU Hao TANG qi heng State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences

In this study, molecular dynamics simulations were carried out to study the effect of machining velocities on the mechanism of chip formation in nano-metric copper. A wide range of cutting velocities was performed from 10 to 2000 m/s, and the microstructure's evolution from a crystalline state to an amorphous state was studied. At the low machining velocity, dislocations were generated from the surface in front of the tool, and the immobile dislocation deduced by the cross slip of dislocation was observed. At the high machining velocity, no crystal dislocation nucleated, but instead disorder atoms were found near the tool. Temperature near the tool region increased with the increasing machining velocities, and the temperature had an important effect on the phase transition of the crystal structure.

关键词： molecular dynamics chip formation machining velocities phase transition

异氰酸酯增强尿素-乙二醛树脂的结构与性能研究

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化学研究与应用 2024年第1期36卷 92-102页

作者：杜旭韬李奇恒汪进文杜官本邓书端云南省木材胶黏剂及胶合制品重点实验室西南林业大学云南昆明650224

为提升尿素-乙二醛树脂(UG)的耐水性能,本研究在UG树脂中添加高活性的异氰酸酯(MDI)共混制备了异氰酸酯/尿素-乙二醛(MDI-UG)木材胶黏剂。采用傅里叶变换红外光谱(FT-IR)、核磁共振波谱仪(NMR)和X射线光电子能谱(XPS)对其固化结构进行表... 详细信息

为提升尿素-乙二醛树脂(UG)的耐水性能,本研究在UG树脂中添加高活性的异氰酸酯(MDI)共混制备了异氰酸酯/尿素-乙二醛(MDI-UG)木材胶黏剂。采用傅里叶变换红外光谱(FT-IR)、核磁共振波谱仪(NMR)和X射线光电子能谱(XPS)对其固化结构进行表征,通过差式扫描量热分析(DSC)、动态热机械分析(DMA)和扫描电镜(SEM)对其固化性能进行分析,以MDI-UG混合体系制备胶合板并测定其力学性能。结果表明UG树脂中含有的活泼氢基团与异氰酸酯反应形成新的氨基甲酸酯;与UG树脂相比,MDI-UG树脂的固化温度降低且热稳定性提高;采用扫描电镜下可观测到MDI-UG树脂的固化颗粒更加密集且交联支化程度明显提高;当MDI的添加量为3%且乙二醛与尿素的摩尔比为1.3:1时,所制得胶合板的热水湿状剪切强度达到0.72 MPa,表明MDI的引入显著改善了UG树脂的耐水性,而且充分发挥了UG树脂优异的环保性能和异氰酸酯的高强度特点。

关键词：尿素-乙二醛树脂异氰酸酯(MDI) 木材胶黏剂结构与性能

铁碳微电解串联天然沸石去除黑臭水体中的总氮

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东北师大学报（自然科学版） 2024年第1期56卷 154-160页

作者：韩东旭刘相汝韩齐恒林山杉东北师范大学环境学院吉林长春130117 吉林省计量科学研究院吉林省计量测试仪器与技术重点实验室吉林长春130103

采用铁碳微电解串联天然沸石技术,研究了去除黑臭水体中总氮的问题.结果表明:(1)通过静态实验确定的最佳处理设计为,进水pH=3,m(Fe)/m(C)比为2∶1,铁碳微电解反应层水力停留时间为120 min,沸石层水力停留时间为40 min,反应柱总的水力停... 详细信息

采用铁碳微电解串联天然沸石技术,研究了去除黑臭水体中总氮的问题.结果表明:(1)通过静态实验确定的最佳处理设计为,进水pH=3,m(Fe)/m(C)比为2∶1,铁碳微电解反应层水力停留时间为120 min,沸石层水力停留时间为40 min,反应柱总的水力停留时间为160 min.(2)动态实验中NH_(4)^(+),NO_(3)^(-)和TN去除率分别保持95%,92%和90%左右,可持续处理300 h以上.(3)中试实验中TN,NO_(3)^(-)和NH_(4)^(+)的平均去除率分别为83.04%,91.85%和88.60%,TP和COD的平均去除率分别为83.2%和89.7%.

关键词：黑臭水体 Fe-C微电解天然沸石总氮去除

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MFF-Net: Multimodal Feature Fusion Network for 3D Object Detection

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Computers, Materials & Continua 2023年第6期75卷 5615-5637页

作者： Peicheng Shi Zhiqiang Liu heng qi Aixi Yang School of Mechanical Engineering Anhui Polytechnic UniversityWuhu241000Anhui ProvinceChina School of Mechanical Polytechnic Institute of Zhejiang UniversityHangzhou310000Zhejiang ProvinceChina

In complex traffic environment scenarios,it is very important for autonomous vehicles to accurately perceive the dynamic information of other vehicles around the vehicle in *** accuracy of 3D object detection will be affected by problems such as illumination changes,object occlusion,and object detection *** this purpose,we face these challenges by proposing a multimodal feature fusion network for 3D object detection(MFF-Net).In this research,this paper first uses the spatial transformation projection algorithm to map the image features into the feature space,so that the image features are in the same spatial dimension when fused with the point cloud ***,feature channel weighting is performed using an adaptive expression augmentation fusion network to enhance important network features,suppress useless features,and increase the directionality of the network to ***,this paper increases the probability of false detection and missed detection in the non-maximum suppression algo-rithm by increasing the one-dimensional *** far,this paper has constructed a complete 3D target detection network based on multimodal feature *** experimental results show that the proposed achieves an average accuracy of 82.60%on the Karlsruhe Institute of Technology and Toyota Technological Institute(KITTI)dataset,outperforming previous state-of-the-art multimodal fusion *** Easy,Moderate,and hard evaluation indicators,the accuracy rate of this paper reaches 90.96%,81.46%,and 75.39%.This shows that the MFF-Net network has good performance in 3D object detection.

关键词： 3D object detection multimodal fusion neural network autonomous driving attention mechanism

3D Vehicle Detection Algorithm Based onMultimodal Decision-Level Fusion

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Computer Modeling in Engineering & Sciences 2023年第6期135卷 2007-2023页

作者： Peicheng Shi heng qi Zhiqiang Liu Aixi Yang School of Mechanical Engineering Anhui Polytechnic UniversityWuhu241000China Department Polytechnic Institute of Zhejiang University Hangzhou310000China

3D vehicle detection based on LiDAR-camera fusion is becoming an emerging research topic in autonomous *** algorithm based on the Camera-LiDAR object candidate fusion method(CLOCs)is currently considered to be a more effective decision-level fusion algorithm,but it does not fully utilize the extracted features of 3D and ***,we proposed a 3D vehicle detection algorithm based onmultimodal decision-level ***,project the anchor point of the 3D detection bounding box into the 2D image,calculate the distance between 2D and 3D anchor points,and use this distance as a new fusion feature to enhance the feature redundancy of the ***,add an attention module:squeeze-and-excitation networks,weight each feature channel to enhance the important features of the network,and suppress useless *** experimental results show that the mean average precision of the algorithm in the KITTI dataset is 82.96%,which outperforms previous state-ofthe-art multimodal fusion-based methods,and the average accuracy in the Easy,Moderate and Hard evaluation indicators reaches 88.96%,82.60%,and 77.31%,respectively,which are higher compared to the original CLOCs model by 1.02%,2.29%,and 0.41%,*** with the original CLOCs algorithm,our algorithm has higher accuracy and better performance in 3D vehicle detection.

关键词： 3D vehicle detection multimodal fusion CLOCs network structure optimization attention module

补肺养心汤联合步行训练对慢性心力衰竭心肺气虚证心功能、心室重构的影响

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中华中医药学刊 2024年第7期42卷 206-210页

作者：李莉英祁珩杨见青严寒郭仙长沙市第一医院湖南长沙410005

目的探讨补肺养心汤联合步行训练对慢性心力衰竭心肺气虚证患者心功能、心室重构的影响。方法选取100例慢性心力衰竭心肺气虚证患者,采用数字表格法随机分为对照组与观察组各50例,两组常规西药规范治疗,对照组同时开展步行训练治疗,观... 详细信息

目的探讨补肺养心汤联合步行训练对慢性心力衰竭心肺气虚证患者心功能、心室重构的影响。方法选取100例慢性心力衰竭心肺气虚证患者,采用数字表格法随机分为对照组与观察组各50例,两组常规西药规范治疗,对照组同时开展步行训练治疗,观察组同时给予补肺养心汤口服联合步行训练治疗,疗程12周,观察治疗前后中医证候积分、心功能及心室重构指标变化。结果两组患者治疗前主症及次症积分比较差异无统计学意义(P>0.05),治疗后积分下降,且观察组下降程度大于对照组,差异均有统计学意义(P0.05),治疗后LVEDD、LVESD、LVPW、IVS下降,且观察组下降程度大于对照组,LVEF、6MWT升高,且观察组升高幅度大于对照组,差异均有统计学意义(P0.05),治疗后NT-proBNP、ET-1、IL-6下降,且观察组下降程度大于对照组,NO升高,且观察组升高幅度大于对照组,差异均有统计学意义;观察组治疗疗效优于对照组(P<0.05)。结论补肺养心汤联合步行训练治疗慢性心力衰竭心肺气虚证可有助于改善患者症状及心功能,抑制心室重构,其机制可能与降低炎性因子水平及调节血管内皮功能有关。

关键词：补肺养心汤步行训练慢性心力衰竭心肺气虚证心功能心室重构

Highly Stereoselective Synthesis of trans-3-Chloro-β-lactams from Imines and Mixed Chloroacetyl and Nitroacetyl Chlorides

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Chemical Research in Chinese Universities 2011年第6期27卷 958-962页

作者： qi heng-zhen MO Shan-yan XU Jia-xi State Key Laboratory of Chemical Resource Engineering Department of Organic Chemistry Faculty of Science Beijing University of Chemical Technology Beijing 100029 P. R. China

A series of trans-3-chloro-β-lactams was synthesized stereospecifically from imines and chloroacetyl chloride or a mixture of chloroacetyl chloride and nitroacetyl chloride, prepared from vinylidene chloride and a mixture of concentrated nitric acid and sulfuric acid, in the presence of triethylamine. The reaction of vinylidene chloride and the mixed acid was investigated. The formation mechanism of chloroacetyl chloride and nitroacetyl chloride and their reaction process with imines were proposed.

关键词： β-Lactam Chloroacetyl chloride Staudinger reaction Stereoselectivity