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Response Mechanisms to Flooding Stress in Mulberry Revealed by Multi-Omics Analysis

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Phyton-International Journal of Experimental Botany 2024年第2期93卷 227-245页

作者： jingtao hu Wenjing Chen Yanyan Duan Yingjing Ru Wenqing Cao Pingwei Xiang Chengzhi huang Li Zhang Jingsheng Chen Liping Gan College of Biology and Food Engineering Chongqing Three Gorges UniversityChongqing404100China Chongqing Three Gorges Academy of Agricultural Sciences Chongqing Three Gorges UniversityChongqing404155China

Abiotic stress,including flooding,seriously affects the normal growth and development of ***(Morus alba),a species known for its flood resistance,is cultivated worldwide for economic *** transcriptomic analysis has identified numerous differentially expressed genes(DEGs)involved in submergence tolerance in mulberry ***,a comprehensive analyses of metabolite types and changes under flooding stress in mulberry remain unreported.A non-targeted metabolomic analysis utilizing liquid chromatographytandem mass spectrometry(LC-MS/MS)was conducted to further investigate the effects of flooding stress on mulberry.A total of 1,169 metabolites were identified,with 331 differentially accumulated metabolites(DAMs)exhibiting up-regulation in response to flooding stress and 314 displaying *** enrichment analysis identified significant modifications in many metabolic pathways due to flooding stress,including amino acid biosynthesis and metabolism and flavonoid *** and DEGs are significantly enriched in the Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways for amino acid,phenylpropanoid and flavonoid ***,metabolites such as methyl jasmonate,sucrose,and D-mannose 6-phosphate accumulated in mulberry leaves post-flooding ***,genes and metabolites associated with these KEGG pathways are likely to exert a significant influence on mulberry flood *** study makes a substantial contribution to the comprehension of the underlying mechanisms implicated in the adaptation of mulberry plants to submergence.

关键词： Mulberry flooding stress flavonoid biosynthesis phenylpropanoid biosynthesis

高阶结构增强的跨视图无负样本对比的图异常检测算法

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计算机科学与探索 2024年第10期18卷 2678-2689页

作者：金虎胡婧韬王思为祝恩罗磊段景灿国防科技大学计算机学院长沙410073 军事科学院智能博弈与决策实验室北京100091

图异常检测在网络安全、金融评估和医疗保健等多个领域都有广泛的实际应用。近年来,基于对比学习和基于生成重构的图异常检测算法框架取得了显著的性能提升。然而,大多数基于图神经网络的范式忽略了一个内在的缺点,即可能会无意识地将... 详细信息

图异常检测在网络安全、金融评估和医疗保健等多个领域都有广泛的实际应用。近年来,基于对比学习和基于生成重构的图异常检测算法框架取得了显著的性能提升。然而,大多数基于图神经网络的范式忽略了一个内在的缺点,即可能会无意识地将异常节点与其邻域正常节点聚合在一起。此外,现有的检测算法缺乏对高阶结构信息的关注,导致正常节点与异常节点之间的判别性下降。为了改善以上缺点,提出了一种高阶结构增强的跨视图无负样本对比的图异常检测算法(CNCL-GAD)。与现有的单视图对比范式不同,提出了以高阶结构信息作为增强视图,通过多视图对比学习方法为图异常检测任务(GAD)引入更多、更丰富的判别信息。为了缓解图异常检测任务中正常样本与异常样本类别不平衡导致的对比负样本对大多数是同一类别的现象,提出了跨视图无负样本对比策略,即只将两个视图之间的正样本子图对拉近。将视图内节点-子图对比模块、属性重构模块和跨视图子图-子图对比模块联合训练,以获得更好的检测性能。在现有的公开数据集上进行了大量实验,与其他竞争算法相比,所提出的算法实现了有竞争力甚至更优越的性能。

关键词：无负样本对比图异常检测高阶结构

Cascaded navigation control for agricultural vehicles tracking straight paths

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International Journal of Agricultural and Biological Engineering 2014年第1期7卷 36-44页

作者： hu jingtao Li Taochang Shenyang Institute of Automation Chinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China

In precision agriculture(PA),an agricultural vehicle navigation system is essential and the navigation control accuracy is important in this *** straight path tracking is the major operating mode of agricultural vehicles on large fields,a cascaded navigation control method for straight path tracking is proposed in this ***,a cascaded navigation control structure for the agricultural vehicle was *** on this structure,the navigation control task was decomposed into two cascaded control tasks,namely,the path tracking control task and the steering control ***,a relative kinematics model of agricultural vehicles was deduced,and an optimal Proportional-Derivative(PD)method based on the deduced model was developed in the path tracking control ***,an improved PD method based on a transition process was proposed in the steering control task to enhance the performance of the steering control ***,the effectiveness and the superiority of the proposed method were verified by a series of *** of the experimental data analysis show that mean value of the lateral position deviation is 0.02 m and standard deviation of the lateral position deviation is 0.04 m,which proves that the proposed method has achieved satisfactory effects on the straight path tracking of agricultural vehicles.

关键词： agricultural vehicle navigation control relative kinematics model optimal PD controller improved PD controller

A sliding-mode variable-structure controller based on exact feedback linearization for automatic navigation system

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International Journal of Agricultural and Biological Engineering 2016年第5期9卷 158-165页

作者： Bai Xiaoping hu jingtao Gao Lei Zhang Tian Shenyang Institute of Automation Chinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China

In order to improve the path tracking accuracy and robustness of the agricultural machinery navigation system,a sliding-mode variable-structure controller based on exact feedback linearization was ***,based on the differential geometry theory and the affine nonlinear kinematics model,the corresponding nonlinear coordinate change matrix and nonlinear state variable feedback equations were deduced,and an exact feedback linearization model was then ***,based on the exact feedback linearization model,a sliding-mode variable-structure controller was designed by selecting suitable linear switching function and exponential reaching ***,the comparative experiments were carried *** the experimental results indicated that the proposed method had a high tracking accuracy and *** maximum lateral error of the straight line tracking was less than 0.06 m,and maximum lateral error of the curve path tracking was less than 0.09 *** results show that the transplanter based on this automatic navigation system can effectively track the predefined path.

关键词： agricultural machine affine nonlinear kinematics model exact feedback linearization sliding-mode variable-structure controller

Development and optimization of a novel grain flow sensor based on PVDF piezoelectric film

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International Journal of Agricultural and Biological Engineering 2016年第4期9卷 141-150页

作者： Wang He hu jingtao Gao Lei Jia Yanfeng Shenyang Institute of Automation Chinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China Information Service and Intelligent Control Department Chinese Academy of Science Shenyang 110016China University of Science and Technology Liaoning Anshan 114051China

A novel grain flow sensor consists of an impact plate and a PVDF(Polyvinylidene Fluoride)piezoelectric film was developed in this *** kinetic model of the grain flow sensor was built to analyze the steady and transient vibration disturbances which had a significant influence on performance of the sensor,and the results showed that damping ratio of the sensor was the key factor to improve accuracy of the *** maximize damping ratio of the sensor,the thickness of the impact plate and damping material were optimized according to a loss factor model of the free damping *** optimized results indicated the most appropriate thickness ratio of damping material and the impact plate was 6.A test rig equipped with the novel grain flow sensor and weight sensors which could simulate field situations was built to investigate the performance of the sensor,on which test experiments under different feed flows were *** results showed that the maximum error of the sensor was 3.02%and the mean error was 2.15%,which revealed that the novel grain flow sensor could be used to measure grain *** with conventional grain flow sensors,the novel grain flow sensor has the features of high accuracy,simple structure and flexible signal processing methods.

关键词： grain flow sensor vibrations free damping structure test rig

复杂底水气藏水侵动态模拟及应用——以元坝长兴组气藏为例

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非常规油气 2024年第5期11卷 10-19页

作者：张明迪符东宇胡景涛景小燕周贵祥中国石化西南油气分公司成都610041

元坝长兴组气藏为局部发育隔夹层的条带状生物礁底水气藏,不同气水分布模式下两相渗流机理复杂,水侵动态认识不深入,控水对策制定缺乏理论指导,严重制约了气藏高产稳产。通过设计流体微观渗流实验,分析不同气水分布模式水侵机理,建立隔... 详细信息

元坝长兴组气藏为局部发育隔夹层的条带状生物礁底水气藏,不同气水分布模式下两相渗流机理复杂,水侵动态认识不深入,控水对策制定缺乏理论指导,严重制约了气藏高产稳产。通过设计流体微观渗流实验,分析不同气水分布模式水侵机理,建立隔层型及无隔层型气井水侵早期预警模型,开展气井见水风险评级,形成差异化控水稳气技术对策。研究成果表明:1)气藏隔层发育使得水侵机理呈现显著差异,考虑复杂气水分布模式能够有效提升水侵动态模拟精度,气井见水时间预测误差可小于10%。2)无隔层型及隔层型2类气水分布模式气井无水采气期的可控因素影响程度由强到弱均为避水高度、生产压差及井筒内径。3)针对无隔层型井区气井,避水高度对气井无水采气期影响趋势与生产压差及井筒内径有显著差异,其影响规模可达另2个因素的3倍以上;隔层型气井无水采气期对于各因素敏感性较无隔层气井显著降低,影响程度变化趋势趋于一致。4)识别气井水侵加剧特征后,应综合考虑底水锥进临界产量及产能来动态调控气井生产压差,延缓水侵速度,元坝气田产水风险井无水采气期平均延长2.3年,控水侵效果显著。以上研究成果有效支撑了元坝气田水侵动态分析及防控对策制定,为同类型气藏高效开发提供技术借鉴。

关键词：元坝气田底水气藏隔夹层水侵动态模拟控水对策

改进的符号时间序列分析方法及其在电机故障诊断中的应用

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仪器仪表学报 2009年第4期30卷 760-766页

作者：胡为胡静涛中国科学院沈阳自动化研究所工业信息学重点实验室沈阳110016 中国科学院研究生院北京100039

提出了一种改进的基于符号时间序列分析的电机异常探测方法,该方法自适应地将符号序列中出现符号最多的符号区间重新划分为2个新的符号区间,使得数据密集区间可以分配到相对更多的符号,而数据稀疏区间则分配到较少的符号,提高了符号对... 详细信息

提出了一种改进的基于符号时间序列分析的电机异常探测方法,该方法自适应地将符号序列中出现符号最多的符号区间重新划分为2个新的符号区间,使得数据密集区间可以分配到相对更多的符号,而数据稀疏区间则分配到较少的符号,提高了符号对于信号变化的灵敏度。电机转子断条故障的诊断实验结果表明:该方法较平均划分区间的方法对于电机异常诊断有着更高的灵敏度以及更好的鲁棒性和可靠性。

关键词：符号时间序列分析故障诊断电机

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旋转机械全息序列相似性匹配故障诊断方法

仪器仪表学报 2009年第3期30卷 536-541页

作者：吴薇胡静涛中国科学院沈阳自动化研究所工业信息重点实验室沈阳110016 中国科学院研究生院北京100039

针对全息诊断分辨率低影响旋转机械故障诊断质量和自动化水平的问题,将时间序列相似性匹配的基本概念和方法引入故障诊断应用中,结合全息诊断信息融合分析旋转机械振动全貌的思想,定义了全息序列及其相似性度量模型,用类时间轴上的多维... 详细信息

针对全息诊断分辨率低影响旋转机械故障诊断质量和自动化水平的问题,将时间序列相似性匹配的基本概念和方法引入故障诊断应用中,结合全息诊断信息融合分析旋转机械振动全貌的思想,定义了全息序列及其相似性度量模型,用类时间轴上的多维序列表征转子系统振动全貌,进而利用采用近似三角不等式与B+树结合剪枝策略的全息序列相似性匹配算法实现故障诊断。实验结果表明,该方法能够实现高质量的故障自动分类识别。

关键词：全息序列故障诊断多维时间序列相似性匹配

基于Smith-模糊PID控制的变量喷药系统设计及试验

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农业工程学报 2014年第8期30卷 56-64页

作者：郭娜胡静涛中国科学院沈阳自动化研究所沈阳110016 中国科学院大学北京100049 中国科学院网络化控制系统重点实验室沈阳110016

为实现精准变量喷药技术,该文设计了旁路节流式变量喷药控制系统用于变量喷药和幅宽调节控制,运用流体网络理论建立系统的数学模型,将模糊PID控制与基于喷药流体网络模型的Smith预估控制结合起来喷药量的调节,并对国产3W-250型喷杆喷雾... 详细信息

为实现精准变量喷药技术,该文设计了旁路节流式变量喷药控制系统用于变量喷药和幅宽调节控制,运用流体网络理论建立系统的数学模型,将模糊PID控制与基于喷药流体网络模型的Smith预估控制结合起来喷药量的调节,并对国产3W-250型喷杆喷雾机进行改造并构建喷药试验平台。试验结果表明,基于喷药流体网络模型的Smith-模糊PID控制算法的动态响应更快,降低了变量喷药系统滞后性和非线性的不利影响,超调量小于13.1%,稳态误差小于3.52%,且具有较好的适应能力和鲁棒性,为精准变量喷药控制提供一种实现方法。

关键词：农业机械喷药模糊控制 Smith预估控制流体网络