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A segmentation method for processing greenhouse vegetable foliar disease symptom images

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Information Processing in Agriculture 2019年第2期6卷 216-223页

作者： Juncheng Ma Keming Du feixiang zheng Lingxian Zhang Zhongfu Sun Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081China College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China

Uneven illumination and clutter background were the most challenging problems to segmentation of disease symptom *** order to achieve robust segmentation,a method for processing greenhouse vegetable foliar disease symptom images was proposed in this *** segmentation method was based on a decision tree which was constructed by a two-step coarse-to-fine ***,a coarse decision tree was built by the CART(Classification and Regression Tree)algorithm with a feature *** feature subset consisted of color features that was selected by Pearson’s Rank ***,the coarse decision tree was optimized by *** the optimized decision tree,segmentation of disease symptom images was achieved by conducting pixel-wise *** order to evaluate the robustness and accuracy of the proposed method,an experiment was performed using greenhouse cucumber downy mildew *** showed that the proposed method achieved an overall accuracy of 90.67%,indicating that the method was able to obtain robust segmentation of disease symptom images.

关键词： Greenhouse vegetables Symptom images Decision tree Image segmentation

Soil warming effect on net ecosystem exchange of carbon dioxide during the transition from winter carbon source to spring carbon sink in a temperate urban lawn

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Journal of Environmental Sciences 2012年第12期24卷 2104-2112页

作者： Xiaoping Zhou Xiaoke Wang Lei Tong Hongxing Zhang Fei Lu feixiang zheng Peiqiang Hou WenzhiSong Zhiyun Ouyang Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeifing 100085China Graduate School of Chinese Academy of Sciences Beijing 100039China

The significant warming in urban environment caused by the combined effects of global warming and heat island has stimulated widely development of urban vegetations. However, it is less known of the climate feedback of urban lawn in warmed environment. Soil warming effect on net ecosystem exchange （NEE） of carbon dioxide during the transition period from winter to spring was investigated in a temperate urban lawn in Beijing, China. The NEE （negative for uptake） under soil warming treatment （temperature was about 5~C higher than the ambient treatment as a control） was -0.71 ~mol/（***）, the ecosytem was a CO2 sink under soil warming treatment, the lawn ecosystem under the control was a CO2 source （0.13 Ixmol/（***））, indicating that the lawn ecosystem would provide a negative feedback to global warming. There was no significant effect of soil warming on nocturnal NEE （i.e., ecosystem respiration）, although the soil temperature sensitivity （Q10） of ecosystem respiration under soil warming treatment was 3.86, much lower than that in the control （7.03）. The CO2 uptake was significantly increased by soil warming treatment that was attributed to about 100% increase of ct （apparent quantum yield） and Amax （maximum rate of photosynthesis）. Our results indicated that the response of photosynthesis in urban lawn is much more sensitive to global warming than respiration in the transition period.

关键词： soil warming urban lawn C02 uptake ecosystem respiration

Preliminary report on methane emissions from the Three Gorges Reservoir in the summer drainage period

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Journal of Environmental Sciences 2011年第12期23卷 2029-2033页

作者： Fei Lu Le Yang Xiaoke Wang Xiaonan Duan Yujing Mu Wenzhi Song feixiang zheng Junfeng Niu Lei Tong Hua zheng Yongjuan Zhou Jiangxiao Qiu Zhiyun Ouyang State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Graduate University of Chinese Academy of Sciences Beijing 100049 China General Office of Chinese Academy of Sciences Beijing 100864 China Laboratory of Atmospheric Chemistry and Air Pollution Control Techniques Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Recently reported summertime methane （CH4） emissions （6.7 ± 13.3 mg CH4/（m2·hr）） from newly created marshes in the drawdown area of the Three Gorges Reservoir （TGR）, China have triggered broad concern in academic circles and among the public. The CH4 emissions from TGR water surfaces and drawdown areas were monitored from 3rd June to 16th October 2010 with floating and static chambers and gas chromatography. The average CH4 emission flux from permanently flooded areas in Zigui, Wushan and Yunyang Counties was （0.33 ± 0.09） mg CH4/（m2·hr）. In half of these hottest months of the year, the wilderness, cropland and deforested drawdown sites were aerobic and located above water level, and the CH4 emissions were very small, ranging from a sink at 0.12 mg CH4/（m2·hr） to a source at 0.08 mg CH4/（m2·hr） except for one mud-covered site after flood. Mean CH4 emission in flooded drawdown sites was 0.34 mg CH4/（m2·hr）. The emissions from the rice paddy sites in the drawdown area were averaged at （4.86 ± 2.31） mg CH4/（m2·hr）. Excepting the rice-paddy sites, these results show much lower emission levels than previously reported. Our results indicated considerable spatial and temporal variation in CH4 emissions from the TGR. Human activities and occasional events, such as flood, may also affect emission levels. Long-term CH4 measurements and modeling in a large region are necessary to accurately estimate greenhouse gas emissions from the TGR.

关键词： methane the Three Gorges Reservoir drawdown area summer drainage uncertainty flood

Application of Semi-active Inerter in a Two-body Point Absorber Wave Energy Converter

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Application of Semi-active Inerter in a Two-body Point Absor...

第三十九届中国控制会议

作者： Zhaoyan Wang Yinlong Hu Sijie Xiong feixiang zheng Haoyu Wang College of Energy and Electrical Engineering Hohai University

This paper studies the application of semi-active inerter in a two-body point absorber wave energy converter. The main idea is to adjust the natural frequencies of the system in accordance with the sea wave frequency by using semi-active inerter to induce resonates, such that the efficiency of wave energy extraction would be enlarged. The optimal inertance and the generator damping coefficient in terms of maximal energy conversion efficiency are analysed, and numerical simulations based on linear wave excitations are conducted. It is demonstrated that matching the natural frequency of the lower float with the low wave frequency is advocated, as in this case, high energy conversion can be obtained（nearly 700% improvement can be obtained by using inerter） and the lifetime of the device can be prolonged due to the mild response of the upper float. The influence of the generator damping coefficient on the energy conversion is also studied, and it is found that the semi-active inerter is advantageous for a low generator damping, and no benefits are found when the generator damping is relatively high.

关键词： Wave energy converter Semi-active Inerter Point absorber

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一种机器人最优加速度轨迹规划算法研究

大连理工大学学报 2017年第2期57卷 177-183页

作者：赵亮仲崇权郑飞翔大连理工大学电子信息与电气工程学部辽宁大连116024 华为数字技术有限公司江苏苏州215000

针对机器人调试过程中遇到的超限问题,提出了一种满足运动约束的加速度最优T型速度曲线控制方法,利用拉格朗日法分析了码垛机器人的动力学性能,论述了机器人轨迹规划算法的实现过程.该算法在保证运动平稳的基础上,充分发挥了驱动关节的... 详细信息

针对机器人调试过程中遇到的超限问题,提出了一种满足运动约束的加速度最优T型速度曲线控制方法,利用拉格朗日法分析了码垛机器人的动力学性能,论述了机器人轨迹规划算法的实现过程.该算法在保证运动平稳的基础上,充分发挥了驱动关节的驱动性能.与传统速度曲线的对比表明,无论单轴还是轴组模式下,机器人的控制效果均得到了明显的提高.

关键词：码垛机器人动力学轨迹规划最优加速度

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基于电子鼻的霉变黄豆和白芸豆检测方法

中国食品学报 2016年第3期16卷 190-197页

作者：郑飞翔李剑楼雄伟惠国华浙江农林大学信息工程学院浙江省林业智能监测与信息技术研究重点实验室浙江临安311300

豆类富含蛋白质、碳水化合物等营养物质,不但可直接烹饪食用,而且可以作为其它食品的原料。在储藏过程中,豆类易受环境的影响而霉变,而霉变豆类中所含霉菌毒素进入体内后将严重损害健康。因此,霉变程度评估对指导豆类储藏具有重要意义... 详细信息

豆类富含蛋白质、碳水化合物等营养物质,不但可直接烹饪食用,而且可以作为其它食品的原料。在储藏过程中,豆类易受环境的影响而霉变,而霉变豆类中所含霉菌毒素进入体内后将严重损害健康。因此,霉变程度评估对指导豆类储藏具有重要意义。本文用黄豆和白芸豆为试验材料,根据豆类霉变所产生的特征气体,合理选用相应的气敏传感器组成阵列,构建用于豆类霉变程度检测的电子鼻系统。采用人工感官方法评价豆类样品的霉变状态。同时使用电子鼻检测不同储藏时间的豆样品,以主成分分析法区分电子鼻检测的试验数据,并采用随机共振方法提取豆类样品的霉变特征值,构建豆类霉变检测模型,用于黄豆和白芸豆样品霉变状态的快速表征。

关键词：黄豆白芸豆霉变状态电子鼻非线性

以溴酸根插层锌铝水滑石为载体构建新溴源体系

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硅酸盐学报 2015年第5期43卷 672-677页

作者：王力耕郑飞翔蒋晨星倪哲明浙江工业大学化学工程学院杭州310032

以溴酸根插层锌铝水滑石(Zn/Al-Br O3–-LDHs)为载体,与Br-等还原剂构建形成新型溴源体系。为实现溴源体系在实际应用中的有效控溴,对Zn/Al-Br O3–-LDHs中Br O3–的释放行为进行了研究,并考察了温度、交换离子类型、p H值等因素对Br O... 详细信息

以溴酸根插层锌铝水滑石(Zn/Al-Br O3–-LDHs)为载体,与Br-等还原剂构建形成新型溴源体系。为实现溴源体系在实际应用中的有效控溴,对Zn/Al-Br O3–-LDHs中Br O3–的释放行为进行了研究,并考察了温度、交换离子类型、p H值等因素对Br O3–释放行为的影响。结果表明:升高温度会加快Br O3–的释放,交换离子的交换性越强,Br O3–释放得越快,在p H值为9.0的磷酸盐缓冲溶液中的释放速率要比在p H值为4.0的磷酸盐缓冲溶液中快。采用4种动力学模型对水滑石中Br O3–的释放过程进行动力学拟合,结果表明:LDHs-Br O3–中Br O3–的释放行为符合Bhaskar方程,属粒内扩散控制过程。用LDHs-Br O3–/Br–构建的溴源体系合成了3,5-二溴-2-氨基苯甲酸甲酯,收率为94.7%,纯度为99.8%。

关键词：溴酸根水滑石释放溴源体系控溴

红心李总可溶性固形物含量的电子鼻预测方法研究

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核农学报 2015年第12期29卷 2360-2365页

作者：李剑郑乐林涵郑飞翔惠国华浙江农林大学信息工程学院/浙江省林业智能监测与信息技术研究重点实验室浙江临安311300

为实现红心李品质的无损检测,采用国标法检测红心李样品的可溶性固形物含量,测定并记录电子鼻响应值,采用非线性随机共振提取电子鼻信噪比特征值,构建红心李总可溶性固形物含量非线性Boltzmann预测模型。结果表明,构建的红心李可溶性固... 详细信息

为实现红心李品质的无损检测,采用国标法检测红心李样品的可溶性固形物含量,测定并记录电子鼻响应值,采用非线性随机共振提取电子鼻信噪比特征值,构建红心李总可溶性固形物含量非线性Boltzmann预测模型。结果表明,构建的红心李可溶性固形物含量预测模型的相关系数R2=0.9700,表明电子鼻可以预测红心李可溶性固形物含量。验证可知,该模型的预测精度较高,对所有测试样品的预测值皆较准确。本研究为果蔬品质电子鼻快速无损检测提供了理论参考。

关键词：红心李总可溶性固形物含量预测电子鼻随机共振信噪比

开顶式气室的内外环境差异及其对小麦生长的影响

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农业环境科学学报 2023年第1期42卷 17-26页

作者：童思思孙旭郑飞翔王效科云南大学生态与环境学院昆明650091 中国科学院生态环境研究中心城市与区域国家重点实验室北京100085 中国科学院北京城市生态系统研究站北京100085 中国农业科学院农业环境与可持续发展研究所北京100081

为探究开顶式气室(Open top chamber,OTC)内外环境差异及其对植物生长的影响,通过对比观测OTC内外的温度、湿度、光合有效辐射以及小麦的净光合速率、生物量、产量,评价了OTC对小麦生长的环境条件及叶片光合速率和产量的影响程度。结果... 详细信息

为探究开顶式气室(Open top chamber,OTC)内外环境差异及其对植物生长的影响,通过对比观测OTC内外的温度、湿度、光合有效辐射以及小麦的净光合速率、生物量、产量,评价了OTC对小麦生长的环境条件及叶片光合速率和产量的影响程度。结果表明:实验通气时间段(9:00—17:00),OTC内部温度比外部高4.8℃(P<0.05),相对湿度低0.6个百分点(P<0.05),光合有效辐射低32.3%(P<0.05)。OTC内小麦的净光合速率显著高于OTC外(P<0.05),且最大影响出现在小麦灌浆阶段。OTC内的小麦单株生物量增加了13.3%,其中穗生物量增加最多(35.2%);小麦单株产量增加了49.2%,其中籽粒数和千粒质量均增加了34.5%。实验结果不仅表明OTC增温能够促进农作物生产并提高产量,而且也提示,若采用OTC开展空气CO_(2)和O_(3)等浓度增加对植物影响模拟实验时,应该尽量减少OTC内外的微气候差异,并考虑OTC增温可能对实验结果的影响。

关键词：开顶式气室小麦气室效应光合作用产量