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基于参考模型横摆率反馈控制的4WS操纵稳定性研究

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农业工程学报 2008年第3期24卷 11-15页

作者：陈杰平易勇乔印虎合肥工业大学机械汽车学院合肥230009 安徽科技学院工学院凤阳233100

随着交通网络发展和车辆速度的提高,4WS车辆及其控制策略的研究日益受到广泛的关注。在分析4WS特点的基础上,建立了4WS系统的二自由度数学模型,提出了基于理想转向模型横摆率反馈控制的思想和控制算法。利用Matlab软件平台,分别对车辆... 详细信息

随着交通网络发展和车辆速度的提高,4WS车辆及其控制策略的研究日益受到广泛的关注。在分析4WS特点的基础上,建立了4WS系统的二自由度数学模型,提出了基于理想转向模型横摆率反馈控制的思想和控制算法。利用Matlab软件平台,分别对车辆行驶速度为20、60和120 km/h的情况进行了仿真研究分析。仿真结果显示,在有效的速度范围内4WS可以很好的地跟踪参考模型,快速达到稳定转向。在高速情况下,普通2WS存在超调且稳定时间较4WS增加88.6%。通过仿真分析比较可知,该文所提出的4WS系统控制方法可以很好地跟踪理想模型横摆角速度,反应灵敏,可有效改善车辆的操纵稳定性,为下一步进行实车试验奠定了理论基础。

关键词： 4WS 反馈控制操纵稳定性参考模型横摆率

An improved EEGNet for single-trial EEG classification in rapid serial visual presentation task

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Brain Science Advances 2022年第2期8卷 111-126页

作者： Hongfei Zhang Zehui Wang yinhu Yu Haojun Yin Chuangquan Chen Hongtao Wang Faculty of Intelligent Manufacturing Wuyi UniversityJiangmen 529020GuangdongChina

As a new type of brain-computer interface(BCI),the rapid serial visual presentation(RSVP)paradigm has attracted significant *** mechanism of RSVP is detecting the P300 component corresponding to the target image to realize fast and correct *** paper proposed an improved EEGNet model to achieve good performance in offline and online ***,the data were filtered by x.AWN to enhance the signal-to-noise ratio of the electroencephalogram(EEG)*** focal loss function was used instead of the cross-entropy loss function to solve the classification problems of unbalanced ***,the subject-specific data were fed to the improved EEGNet model to obtain a subject-specific *** applied the proposed model at the BCI Controlled Robot Contest in World Robot Contest 2021 and won the second *** average recall rate of the four participants reached 51.56%in triple *** the offline data benchmark dataset(64 subjects-RSVP tasks),the average recall rates of groups A and B reached 76.07%and 78.11%,*** provided an alternative method to identify targets based on the RSVP paradigm.

关键词： electroencephalogram rapid serial visual presentation event-related potential EEGNet subject-specific model

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多高层钢结构住宅结构体系研究浅谈

工业建筑 2007年第Z1期37卷 676-678页

作者：梁印虎杭州恒达钢结构实业有限公司杭州311215

对多高层钢结构住宅研究的结构体系进行简要介绍,同时介绍杭州恒达钢结构实业有限公司针对钢结构住宅体系开发的专利节点——隔板贯通式梁柱节点的研究成果。

关键词：钢结构住宅结构体系隔板贯通式梁柱节点

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火药启动器壳体瞬态温度场的数值模拟分析

导弹与航天运载技术 2012年第1期 7-12页

作者：王寅虎北京航天动力研究所北京100076

通过对某型号火箭发动机的火药启动器单独工作时壳体的瞬态温度场进行计算和分析,研究了燃气热效应对电爆管电缆插头非金属部分的影响;通过使用Fluent软件对发动机火药启动器工作期间壳体瞬态温度场进行数值模拟,同时对圆柱段进行一维... 详细信息

通过对某型号火箭发动机的火药启动器单独工作时壳体的瞬态温度场进行计算和分析,研究了燃气热效应对电爆管电缆插头非金属部分的影响;通过使用Fluent软件对发动机火药启动器工作期间壳体瞬态温度场进行数值模拟,同时对圆柱段进行一维传热计算,得到火药启动器工作1 s后的内外壁面温度分布,并与实验数据进行对比分析。结果表明,使用Fluent软件数值模拟和一维传热计算得到的火药启动器工作后的壁面温度相近,且与实验测量数据相差不大,火药启动器单独工作的热效应对电爆管电缆插头非金属部分没有影响。

关键词：固体火箭发动机火药启动器电爆管瞬态温度场数值模拟

Investigation on Outbreak of Sesamia inferens and Smut in Cane-growing Regions of Yunnan Province

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Agricultural Biotechnology 2023年第2期12卷 63-66,72页

作者： Yongde MA x.aoyan WANG yinhu LI Hongli SHAN Rongyue ZHANG Yingkun HUANG Agricultural and Rural Affairs Bureau of Gengma County Gengma 677500China Sugarcane Research Institute Yunnan Academy of Agricultural SciencesKaiyuan 661699China

[Objectives]This study was conducted to clarify the outbreak and disaster characteristics of Sesamia inferens Walker and smut in cane-growing regions in the low-latitude plateau of Yunnan Province,where there is continuous high temperature and drought in spring and summer.[Methods]A systematic investigation and analysis was conducted on different varieties in different types of fields in 16 cane-growing regions with outbreak of *** and smut in Yunnan from 2019 to 2021.[Results]The outbreak of *** and smut in cane-growing regions in the low-latitude plateau of Yunnan Province resulted in an average percent of dry hearts in the range of 17.3%-56.3%,and as high as 84.0%in severe cases.70%thiamethox.m seed treatment dispersible powder and clothianidin or thiamethox.m fertilizer granules were ineffective against ***,while 10%monosultap·thiamethox.m or 10%clothianidin·monosultap granules had a significant control efficacy on *** average diseased plant rate ranged from 14.8%to 89.7%in susceptible varieties with smut,and was as high as 100%in severe *** 1,Yuetang 93-159,Yuetang 00-236,and Liucheng 05-136 had strong resistance,with an average diseased plant rate of 0-5.5%and the highest rate of 7.6%.*** and smut both broke out in cane-growing regions with an altitude below 1200 *** is recommended to pay attention to disease and pest monitoring in cane-growing regions with an altitude below 1200 m,and combine it with the management of new plants and ratoon plants to effectively prevent and control the first and second generation of ***-infested seedlings from March to *** is also recommended to strengthen the promotion and application of ex.ellent disease-resistant varieties,so as to achieve a reasonable distribution of varieties and fundamentally control the outbreak and epidemic of sugarcane smut.[Conclusions]This study provides a basis for the effective prevention and control of catastrophic *** and smut caused

关键词： High temperature Drought Sesamia inferens Smut Outbreak

Nanometer-sized Zirconium ox.de Immobilized on Silica Gel Separation/Preconcentration and Flame Atomic Absorption Spectrometric Determination of Trace Cadmium in Water Samples

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Nanometer-sized Zirconium oxide Immobilized on Silica Gel Se...

Detection and Identification of Sugarcane Pokkah Boeng Pathogens of Main Sugarcane Varieties in Yunnan Province

中国化学会第十三届全国分析化学年会

作者： Binwu Yang Liping Zhao Zhaorong Liu yinhu Yu Chenzhong Yao Department of Applied Chemistry Yuncheng University

Silica gel was prepared by the sol-gel,modified with nanometer-sized zirconium ox.de(ZrO/SiO),and this material was characterized by x.ray diffraction and Fourier transform infrared spectroscopy (FT-IR).Nanosized Zr O/SiO composites as solid phase ex.raction sorbent was developed for the separation and preconcentration of trace amounts of cadmium prior to their determination by flame atomic absorption *** effect factors of the proposed method were investigated *** was found that Cdcould be adsorbed quantitively on the sorbent when the pH ex.eeded 4.0～7.0,and 0.05 mol/L HNO was sufficient for complete *** adsorption capacity for cadmium was found to be 6.29 mg/*** detection limit for Cdwas 3.18μg/L with an enrichment factor of *** relative standard deviation was 2.1%(n=7,c=5.0μg/mL).The proposed method has been applied for the determination of trace Cdin real water samples with satisfactory results.

关键词： Cadmium ZrO2/SiO2 FAAS Water samples

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Agricultural Biotechnology 2022年第6期11卷 43-47页

作者： x.aoyan WANG Wenfeng LI yinhu LI Hongli SHAN Rongyue ZHANG Yingkun HUANG Key Laboratory on Genetic Improvement of Sugarcane in Yunnan Province Sugarcane Research InstituteYunnan Academy of Agricultural SciencesKaiyuan 661699China

[Objectives]This study was conducted to identify the pathogen species and dominant species of sugarcane pokkah boeng in main varieties in Yunnan sugarcane areas,so as to promote the healthy and sustainable development of sugarcane industry.[Methods]Specific primers Fv-F3/Fv-R3 and Fp-F4/Fp-R4 were designed based on the ribosomal DNA non-internal transcribed spacer(rDNA-ITS)gene sequences of Fusarium verticillioides and Fusarium proliferarum,the main pathogens of sugarcane pokkah boeng,and 117 typical sugarcane pokkah boeng samples collected from main varieties in different sugarcane areas of Yunnan Province were detected and analyzed by PCR.[Results]Among the 117 sugarcane pokkah boeng samples,112 samples were detected with *** with a positive detection rate of 95.7%;103 samples were detected with *** with a positive detection rate of 88%;103 samples were infected by ***+***,and the compound infection rate was 88%;and the two pathogens were not detected in 5 samples,which might be sugarcane pokkah boeng caused by other *** amplification products of 23 *** positive samples and 19 *** positive samples from different sugarcane varieties in different sugarcane areas were *** BLAST alignment results showed that the sequences of the 23 amplification products of *** shared 99.45%-100.00%homology with ***(GenBank accession number:KU508286),and the sequences of the 19 amplification products of *** shared 99.26%-100.00%homology with the sequence of ***(GenBank accession number:MK252904).Part of the *** and 11 *** sequences were selected to construct a phylogenetic tree,and the phylogenetic analysis showed that they belonged to the *** group and *** group,*** results showed that *** and *** were the main pathogens causing sugarcane pokkah boeng of the

关键词： Sugarcane pokkah boeng Pathogens Dominant species Main varieties PCR detection Phylogenetic analysis

Ag-CuO触点材料侵蚀过程的演化动力学及力学性能

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金属学报 2022年第10期58卷 1305-1315页

作者：马敏静屈银虎王哲王军杜丹西安工程大学材料工程学院西安710048 西安交通大学物理学院西安710049

基于Ag-45CuO(骨架Ag-CuO)和Ag-20CuO(岛状Ag-CuO)触点材料的微观结构特征,利用物相识别结合显微结构分析重建了Ag-CuO材料的三维尺度模型,采用计算流体动力学(CFD)方法模拟了侵蚀作用下CuO微观结构的动态演变和重构过程。实验和模拟结... 详细信息

基于Ag-45CuO(骨架Ag-CuO)和Ag-20CuO(岛状Ag-CuO)触点材料的微观结构特征,利用物相识别结合显微结构分析重建了Ag-CuO材料的三维尺度模型,采用计算流体动力学(CFD)方法模拟了侵蚀作用下CuO微观结构的动态演变和重构过程。实验和模拟结果表明,反复的热冲击导致岛状Ag-CuO熔池表面形成火山口状凹坑,而骨架Ag-CuO熔池表面较为光滑。这是由于骨架Ag-CuO触点局部间隙作为CuO骨架重构的驱动力,可使重构后的CuO呈现出更明显的各向异性,从而有效束缚熔池中Ag的蒸发与偏析;而岛状Ag-CuO触点开断过程并未发生明显的CuO重构现象,其基体内岛状CuO结构易使触点在反复侵蚀作用下失效。随后,利用视觉识别技术结合有限元法,逆向重建了骨架Ag-CuO和岛状Ag-CuO触点表层局部的三维模型,进一步研究了CuO微观结构对触点表层力学性能的影响。结果表明,相比于岛状CuO结构,骨架CuO结构的相界面处不易产生应力和应变集中,该结构可有效分散熔池表面局部冲击力,显著提高触点的抗侵蚀性能。

关键词： Ag-CuO触点材料抗侵蚀特性骨架重构微观结构演变力学性能

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鱼眼相机矢量观测检校模型及其应用

测绘学报 2016年第3期45卷 332-338页

作者：詹银虎郑勇张超骆亚波王凯信息工程大学导航与空天目标工程学院河南郑州450001 郑州大学水利与环境学院河南郑州450001 总装备部工程设计研究总院北京100028

提出了一种基于矢量观测的鱼眼相机检校新模型。该模型中的基本观测量不仅包括半视场角,而且包括方位角。在模型中引入罗德里格矩阵,采用3个罗德里格参数表示外方位元素,简化了观测方程的形式及运算。采用实测的星图数据对新模型与基于... 详细信息

提出了一种基于矢量观测的鱼眼相机检校新模型。该模型中的基本观测量不仅包括半视场角,而且包括方位角。在模型中引入罗德里格矩阵,采用3个罗德里格参数表示外方位元素,简化了观测方程的形式及运算。采用实测的星图数据对新模型与基于半视场角约束的检校模型进行比较,结果表明新模型在约束方位角误差方面具有明显的优势,在约束半视场角误差方面略有不足。建议在实际应用中首先采用基于半视场角约束的检校模型确定径向畸变参数,然后再采用新模型求解其他相机参数。

关键词：天文导航鱼眼相机相机检校罗德里格矩阵精度估计