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Development of Spectral Features for Monitoring Rice Bacterial Leaf Blight Disease Using Broad-Band Remote Sensing Systems

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Phyton-International Journal of Experimental Botany 2024年第4期93卷 745-762页

作者： jingcheng zhang Xingjian Zhou Dong Shen Qimeng Yu Lin Yuan Yingying Dong College of Artificial Intelligence Hangzhou Dianzi UniversityHangzhou310018China School of Information Engineering Zhejiang University of Water Resources and Electric PowerHangzhou310018China Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing100094China

As an important rice disease, rice bacterial leaf blight (RBLB, caused by the bacterium Xanthomonas oryzae ***), has become widespread in east China in recent years. Significant losses in rice yield occurred as a result ofthe disease’s epidemic, making it imperative to monitor RBLB at a large scale. With the development of remotesensing technology, the broad-band sensors equipped with red-edge channels over multiple spatial resolutionsoffer numerous available data for large-scale monitoring of rice diseases. However, RBLB is characterized by rapiddispersal under suitable conditions, making it difficult to track the disease at a regional scale with a single sensorin practice. Therefore, it is necessary to identify or construct features that are effective across different sensors formonitoring RBLB. To achieve this goal, the spectral response of RBLB was first analyzed based on the canopyhyperspectral data. Using the relative spectral response (RSR) functions of four representative satellite or UAVsensors (i.e., Sentinel-2, GF-6, Planet, and Rededge-M) and the hyperspectral data, the corresponding broad-bandspectral data was simulated. According to a thorough band combination and sensitivity analysis, two novel spectralindices for monitoring RBLB that can be effective across multiple sensors (i.e., RBBRI and RBBDI) weredeveloped. An optimal feature set that includes the two novel indices and a classical vegetation index was *** capability of such a feature set in monitoring RBLB was assessed via FLDA and SVM algorithms. The resultdemonstrated that both constructed novel indices exhibited high sensitivity to the disease across multiple ***, the feature set yielded an overall accuracy above 90% for all sensors, which indicates its cross-sensorgenerality in monitoring RBLB. The outcome of this research permits disease monitoring with different remotesensing data over a large scale.

关键词： Rice bacterial leaf blight analysis of spectral response multispectral data simulation vegetation indices cross-sensor disease monitoring

基于空间偏振混叠特性的红外偏振视频目标跟踪

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兵工学报 2024年第9期45卷 3274-3287页

作者：乔新博赵永强张景程西北工业大学自动化学院陕西西安710072

基于分焦平面的红外偏振摄像仪体积小、实时性好、精确度高,并能有效应对复杂天候与红外伪装等干扰,但输出的偏振马赛克视频需要去马赛克并计算偏振参数,这种耗时较长且存在误差的处理方式限制了该设备在实时目标跟踪领域的应用。为解... 详细信息

基于分焦平面的红外偏振摄像仪体积小、实时性好、精确度高,并能有效应对复杂天候与红外伪装等干扰,但输出的偏振马赛克视频需要去马赛克并计算偏振参数,这种耗时较长且存在误差的处理方式限制了该设备在实时目标跟踪领域的应用。为解决这一问题,分析了红外偏振马赛克图像中空间信息与偏振信息的混叠特性,提出基于空间偏振混叠梯度的马赛克图像空间偏振梯度方向直方图特征。特征利用偏振通道之间的空间相关性,设计空间梯度算子获取图像的空间信息,并利用偏振伪全色图像与偏振通道之间的关联性设计偏振梯度算子,结合图像空间信息与偏振信息构建目标特征。将该特征应用于AutoTrack目标跟踪方法,实现了基于空间-偏振混叠信息的实时红外偏振视频目标跟踪。在实拍的红外偏振马赛克视频数据上的实验结果表明,该特征提取方法可提高红外偏振图像的目标跟踪实时性和准确性,并有效利用马赛克图像的偏振信息。

关键词：偏振图像特征提取目标跟踪空间偏振混叠梯度

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血清actinin-4、TFF1及TGFBI水平对原发性肝癌患者经导管动脉化疗栓塞术后预后的预测

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中国临床研究 2024年第6期37卷 880-884页

作者：耿蕴峰张景承薛菲王冬冬河北医科大学附属人民医院石家庄市人民医院普外二科河北石家庄050000

目的探讨血清辅肌动蛋白4(actinin-4)、三叶因子1(TFF1)、转化生长因子β诱导蛋白(TGFBI)对原发性肝癌(PHC)患者经导管动脉化疗栓塞(TACE)术后预后的预测价值。方法以2020年1月至2023年5月在石家庄市人民医院进行TACE治疗的312例PHC患... 详细信息

目的探讨血清辅肌动蛋白4(actinin-4)、三叶因子1(TFF1)、转化生长因子β诱导蛋白(TGFBI)对原发性肝癌(PHC)患者经导管动脉化疗栓塞(TACE)术后预后的预测价值。方法以2020年1月至2023年5月在石家庄市人民医院进行TACE治疗的312例PHC患者为研究对象(PHC组),根据患者术后情况将PHC患者分为预后良好组(n=252)和预后不良组(n=60),另选取同期行健康检查者312例为对照组。ELISA法测定所有受试者血清actinin-4、TFF1、TGFBI水平。Logistic回归分析PHC患者TACE术后预后不良的影响因素;受试者工作特征曲线(ROC)分析血清actinin-4、TFF1、TGFBI对PHC患者TACE术后预后不良的预测价值。结果预后良好组与预后不良组在性别、年龄、Child-Pugh分级及临床分期上差异无统计学意义(P>0.05),在肿瘤大小、门静脉癌栓上差异有统计学意义(P<0.05)。与对照组相比,PHC组患者血清actinin-4[(45.67±10.23)pg/mL vs(28.25±6.96)pg/mL,t=24.868,P<0.01]、TFF1[(5.04±1.53)ng/mL vs(2.32±0.64)ng/mL,t=28.969,P<0.01]、TGFBI[(19.16±4.36)ng/mL vs(10.25±2.43)ng/mL,t=31.530,P<0.01]水平更高。与预后良好组相比,预后不良组患者血清actinin-4、TFF1、TGFBI水平均显著升高(P<0.01)。多因素logistic回归分析结果显示,肿瘤大小、门静脉癌栓、血清actinin-4、TFF1、TGFBI均为PHC患者TACE术后预后的影响因素(P<0.05)。ROC曲线结果显示,血清actinin-4、TFF1、TGFBI联合预测PHC患者TACE术后预后的AUC为0.926,敏感度为81.3%,特异度为76.8%。结论PHC患者TACE术后预后不良患者血清actinin-4、TFF1、TGFBI水平均显著升高,且三者联合测定对患者预后具有良好的预测价值。

关键词：原发性肝癌动脉化疗栓塞术辅肌动蛋白4 三叶因子1 转化生长因子β诱导蛋白

In situ FT-IR spectroscopy investigations of carbon nanotubes supported Co-Mo catalysts for selective hydrodesulfurization of FCC gasoline

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Journal of Natural Gas Chemistry 2008年第2期17卷 165-170页

作者： jingcheng zhang Wenkun Yin Hongyan Shang Chenguang Liu State Key Laboratory of Heavy Oil Processing Key Laboratory of Catalysis CNPC College of Chemistry ＆ Chemical Engineering China University of Petroleum. Dongying 257061 Shangdong China

To better understand the nature of carbon nanotubes supported Co-Mo catalysts （Co-Mo/CNTs） for selective hydrodesulfurization （HDS） of fluid catalytic cracking （FCC） gasoline, studies are carried out using in situ Fourier transform infrared spectroscopy （FT-IR）. The catalytic performances of Co-Mo/CNTs catalysts were evaluated with a mixture of cyclohexane, diisobutylene, cyclohexene, 1-octene （60 ： 30 ： 5 ： 5, volume ratio） and thiophene （0.5%, ratio of total weight） as model compounds to simulate FCC gasoline. The HDS experimental results suggested that the HDS activity and selectivity of Co-Mo/CNTs catalysts were affected by Co/Mo ratio; the optimal Co/Mo atomic ratio is about 0.4, and the optimum reaction temperature is 260 ℃. The in situ FT-IR studies revealed that 1-octene can be completely saturated at 200 ℃. In the FT-IR spectra of diisobutylene, the characteristic absorption peak around 3081 cm^-1 for the stretching vibration peak of =C-H bond was still clear at 320 ℃ indicating that diisobutylene is difficult to be hydrogenated. As for the thiophene, no characteristic absorption peak could be found around 3092 cm^-1 and 835 cm^-1 when the reaction temperature was raised to 280 ℃, indicating that thiophene had been completely hydrodesulfurized. On the basis of FT-IR results, it can be deduced that thiophene HDS reaction occurred mainly through direct hydrogenolysis route, whereas thiophene HDS and diisobutylene hydrogenation reaction over Co-Mo/CNTs catalysts might occur on two different kinds of active sites.

关键词： in situ FT-IR hydrodesulfurization carbon nanotubes hydrogenolysis thiophene FCC gasoline

Reactive adsorption of thiophene on Ni/ZnO adsorbent:Effect of ZnO textural structure on the desulfurization activity

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Journal of Natural Gas Chemistry 2010年第3期19卷 327-332页

作者： jingcheng zhang Yunqi Liu Shuang Tian Yongming Chai Chenguang Liu State Key Laboratory of Heavy Oil Processing Key Laboratory of Catalysis CNPC China University of Petroleum Qingdao 266555 Shandong China

To better understand the nature of reactive adsorption of thiophene on Ni/ZnO adsorbent,the effect of ZnO textural structure on the desulfurization activity was *** materials were synthesized by low-temperature solid-state reaction and the corresponding Ni/ZnO adsorbents were prepared by incipient impregnation *** analysis results showed that the crystalline sizes of ZnO as-synthesized as well as the BET surface areas varied obviously with the calcination *** activity evaluations indicated that the Ni/ZnO adsorbents prepared with ZnO possessed a favorable textural structure as active component exhibited good activity of removing *** evolutions of the main crystalline phases of Ni/ZnO adsorbents before and after reaction confirmed that ZnO played a crucial role in taking up S element and converting it into ZnS in the reactive adsorption *** was concluded that ZnO with larger surface area and smaller crystal particles resulted in better desulfurization activity,which may be the main reason for the different activities of the Ni/ZnO adsorbents prepared with ZnO calcined at different temperatures.

关键词： Ni/ZnO reactive adsorption textural structure low-temperature solid-state reaction thiophene

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基于多尺度数据集的虫害检测模型

农业工程学报 2024年第5期40卷 196-206页

作者：陈冬梅林佳王海亮吴开华陆玉恒周晓飞张竞成杭州电子科技大学自动化学院杭州310018 杭州睿坤科技有限公司杭州310018

在复杂和密集尺度的农业检测任务中基于Transformer的DETR类模型逐渐崭露头角,但现有的传统量化分析难以深入探究检测模型的优化策略和机制的有效性。为了满足密集小型昆虫的检测和计数的需求,该研究构建了真实场景采集的包含稻飞虱、... 详细信息

在复杂和密集尺度的农业检测任务中基于Transformer的DETR类模型逐渐崭露头角,但现有的传统量化分析难以深入探究检测模型的优化策略和机制的有效性。为了满足密集小型昆虫的检测和计数的需求,该研究构建了真实场景采集的包含稻飞虱、蚜虫和麦蜘蛛3类小型害虫的多尺度虫害数据集(multi-scale tiny crowded planthopper-aphid-wheat mite pest detection,MTC-PAWPD),提出基于黏连率和相对尺寸的数据划分方式,将虫害数据集分为密集分布、大尺度、中小尺度和超小尺度4类场景。通过分析DINO模型在特定场景下的性能表现,设计详尽的消融试验方案,以特征与其关键组件查询的可视化试验辅助,验证虫害检测任务性能提高与各个模块之间尤其是与查询相关模块的联系。经试验,模型在MTC-PAWPD测试集上的mAP@50达70.0%,与其他主流模型相比提升2.3个百分点。在4类场景中mAP@50分别达42.5%、79.4%、75.7%和62.4%,在多尺度、密集任务中表现出较强的检测性能。通过针对自身模块的消融和可视化试验证明模型性能提升与Transformer部分的优化模块相关性更大。试验说明基于DINO的虫害检测模型在田间复杂背景下多尺度的复杂虫害检测任务中具有强大的泛化能力和实用价值。

关键词：目标检测模型 Transformer 虫害深度学习

Effects of different atmospheres on the arc erosion behaviors of Ti_(3)SiC_(2)cathodes

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Science China(Technological Sciences) 2021年第3期64卷 620-628页

作者： ZHOU ZiJue FENG Yi ZHAO Hao QIAN Gang zhang jingcheng zhang XueBin HUANG XiaoChen School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China Instrumental Analysis Center Hefei University of TechnologyHefei 230009China School of Material and Chemical Engineering Bengbu UniversityBengbu 233030China

The effects of ambient atmospheres on the arc erosion behaviors of Ti_(3)SiC_(2)cathodes were investigated at 5.5 kV in argon,nitrogen,air,and *** mass loss of the cathodes increased in the order of argon,nitrogen,air,and oxygen and the morphologies were measured by 3D laser scanning confocal microscope with a gradual blooming *** spectroscopy,X-ray diffraction,and X-ray photoelectron spectroscopy were employed to detect the components of erosion *** erosion-chemical products mainly consisted of TiNx in nitrogen,TiN_(x),TiO_(2)and SiO_(2)in air,TiO_(2)and SiO_(2)in *** arc energy was responsible for the arc erosion characteristics in different atmospheres.

关键词： Ti_(3)SiC_(2) atmosphere arc erosion

Arc corrosion behavior of Cu-Ti_3AlC_2 composites in air atmosphere

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Science China(Technological Sciences) 2018年第4期61卷 551-557页

作者： HUANG XiaoChen FENG Yi QIAN Gang ZHAO Hao SONG ZhaoKun zhang jingcheng zhang XueBin School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China Instrumental Analysis Center Hefei University of TechnologyHefei 230009China

The arc corrosion evolution of Cu-20 vol.% Ti_3 AlC_2 cathodes is presented here. After eroded by 3, 4, 5, 6, 7, 8, 9, 10 kV DC voltage, respectively, the surface morphologies were characterized by field emission scanning electron microscope with craters and protrusions. Compared to small craters and dense protrusions of the morphology by high voltage, the eroded surface was covered with bigger craters and sparse protrusions at low voltage. No crack was discovered on the surface even at 10 kV. By means of energy dispersive spectroscopy and Raman spectroscopy, the decomposition of Cu-20 vol.% Ti_3 AlC_2 cathode to CuO,Al__2 O_3 and TiO_2 were proved. Meanwhile, W anode is oxidized to WO_2. The peak current increases with the increasing breakdown voltage, which is recorded by a digital memory oscilloscope.

关键词： Cu-Ti_3AlC_2 arc erosion FE-SEM Raman spectroscopy

The continuous wavelet projections algorithm: A practical spectral-feature-mining approach for crop detection

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The Crop Journal 2022年第5期10卷 1264-1273页

作者： Xiaohu Zhao jingcheng zhang Ruiliang Pu Zaifa Shu Weizhong He Kaihua Wu College of Artificial Intelligence Hangzhou Dianzi UniversityHangzhou 310018ZhejiangChina School of Geosciences University of South FloridaTampaFL 33620USA Lishui Institute of Agriculture and Forestry Sciences Lishui 323000ZhejiangChina

Spectroscopy can be used for detecting crop characteristics. A goal of crop spectrum analysis is to extract effective features from spectral data for establishing a detection model. An ideal spectral feature set should have high sensitivity to target parameters but low information redundancy among ***, feature-selection methods that satisfy both requirements are lacking. To address this issue,in this study, a novel method, the continuous wavelet projections algorithm(CWPA), was developed,which has advantages of both continuous wavelet analysis(CWA) and the successive projections algorithm(SPA) for generating optimal spectral feature set for crop detection. Three datasets collected for crop stress detection and retrieval of biochemical properties were used to validate the CWPA under both classification and regression scenarios. The CWPA generated a feature set with fewer features yet achieving accuracy comparable to or even higher than those of CWA and SPA. With only two to three features identified by CWPA, an overall accuracy of 98% in classifying tea plant stresses was achieved, and high coefficients of determination were obtained in retrieving corn leaf chlorophyll content(R^(2)= 0.8521)and equivalent water thickness(R^(2)= 0.9508). The mechanism of the CWPA ensures that the novel algorithm discovers the most sensitive features while retaining complementarity among features. Its ability to reduce the data dimension suggests its potential for crop monitoring and phenotyping with hyperspectral data.

关键词： Hyperspectral Crop parameters Crop phenotyping Continuous wavelet analysis Successive projections algorithm