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Recognition of cotton growth period for precise spraying based on convolution neural network

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Information Processing in Agriculture 2021年第2期8卷 219-231页

作者： Shanping Wang Yang Li Jin Yuan Laiqi Song Xinghua liu xuemei liu College of Mechanical&Electronic Engineering Shandong Agricultural UniversityTai’an 271018China Shandong Provincial Key Laboratory of Horticultural Machinery and Equipment Tai’an 271018China

Dynamic acquisition of crop morphology is beneficial to real-time variable decision of precise spraying operations in ***,the existing spraying quantity regulation has high tolerance on the statistical characteristics of regional morphology,so expensive LiDAR and ultrasonic radar can’t make full use of their high accuracy,and can reduce decision speed because of too much detail of branches and ***,designing a novel recognition system embedded machine learning with low-cost monocular vision is more feasible,especially in China,where the agricultural implements are medium sizes and *** addition,we found that the growth period of crops is an important reference index for guiding ***,taking cotton as a case study,a cotton morphology acquisition by a single camera is established,and a cotton growth period recognition algorithm based on Convolution Neural Network(CNN)is proposed in this *** the optimization process based on confusion matrix and recognition efficiency,an optimized CNN model structure is determined from 9 different model structures,and its reliability was verified by changing training sets and test sets many times based on the idea of kfold *** accuracy,precision,recall,F1-score and recognition speed of this CNN model are 93.27%,95.39%,94.31%,94.76%and 71.46 ms per image,*** addition,compared with the performance of VGG16 and AlexNet,the convolution neural network model proposed in this paper has better ***,in order to verify the reliability of the designed recognition system and the feasibility of the spray decision-making algorithm based on CNN,spraying deposition experiments were carried out with 3 different growthperiods of *** experiments’results validate that after the optimal spray parameters were applied at different growth periods respectively,the average optimum index in 3 growth periods was 42.29%,which was increased up to 62.24%than the operations wit

关键词： Precision spraying Growth period of cotton Target perception Convolution neural network Image classification

High-temperature mechanical behavior of ultra-coarse cemented carbide with grain strengthening

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Journal of Materials Science & Technology 2022年第9期104卷 8-18页

作者： Huaxin Hu xuemei liu Jinghong Chen Hao Lu Chao liu Haibin Wang Junhua Luan Zengbao Jiao Yong liu Xiaoyan Song Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China Xiamen Tungsten Co. Ltd.Xiamen 361009China Department of Materials Science and Engineering City University of Hong KongHong KongChina Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHong KongChina State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Ultra-coarse grained cemented carbides are often used under conditions of concurrently applied stress and high *** of high-temperature mechanical performance of ultra-coarse grained cemented carbides is highly desirable but still a big *** this study,it is proposed that the hightemperature compression strength of ultra-coarse cemented carbides can be enhanced by modulating hard matrix grains by activated Ta C nanoparticles,through solid solution strengthening of Ta *** on the designed experiments and microstructural characterizations combined with finite element simulations,the grain morphology,stress distribution and dislocation configuration were studied in detail for ultra-coarse grained cemented *** mechanisms of Ta dissolving in WC crystal and strengthening ultra-coarse grains through interaction with dislocations were disclosed from the atomic *** study opens a new perspective to modulate hard phases of cemented carbides for improving their hightemperature performance,which will be applicable to a variety of cermet and ceramic-based composite materials.

关键词： Ultra-coarse cemented carbides High-temperature compressive behavior Strengthening of hard-phase grains Dislocation motion

Anode material with Li-Si nano-domains in three-dimensional carbon network

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Progress in Natural Science:Materials International 2019年第3期29卷 310-315页

作者： Chao Hou Ke Yang Fawei Tang Haibin Wang xuemei liu Xiaoyan Song College of Materials Science and Engineering Key Laboratory of Advanced Functional Materials Education Ministry of China Beijing University of Technology

A micro-nano combined composite with Li-Si alloy nano-domains in three-dimensional carbon network was prepared as a novel electrode *** carbon network constrained the volume contraction and promoted effectively charge transfer of the whole active ***,the abundant interfaces between Li-Si alloy and carbon bound by Li-C ionic bonds,not only enhanced the delithiation at interface but also ensured the structural *** present composite exhibited excellent electrochemical *** specific capacity at the first lithiation was as high as 1133 mAh g-1at a current density of 0.1 A g-1,which is superior to those reported for the core-shell structured *** Coulombic Efficiency at the first cycle was 90.4%and kept stable at more than 99.0%after only 10 *** capacity retention was nearly twice as that of the incompact mixture of Li-Si nanoparticles and *** energy density of the full cell constructed by the present composite and sulfur was evaluated to be 3 times as high as that of the commercial lithium-ion *** work provides a new universal strategy for developing Li-rich anode materials with high combination properties and low cost.

关键词： Li-Si alloy Three-dimensional carbon network Nano-domain Interface bond

Subrecoil cooling of ^(6)Li atoms by 2S→3P ultraviolet narrow transition

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Science China(Physics,Mechanics & Astronomy) 2023年第8期66卷 36-41页

作者： Yang Rui Liang Zhang Rui Li Pengyue liu xuemei liu Chunyang Duan Shichuan Yu Yuelong Wu Haibin Wu State Key Laboratory of Precision Spectroscopy Institute of Quantum Science and Precision MeasurementEast China Normal UniversityShanghai 200062China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Shanghai Research Center for Quantum Sciences Shanghai 201315China

Laser cooling of atoms and molecules is crucial to exhibiting excellent features in the field of low-temperature *** ^(6)Li atoms to very low temperatures is difficult due to their partially resolved D_(2) line of excited *** we report an observation of cooling ^(6)Li atom samples to 16μK with an ultraviolet(UV)laser in a magneto-optical trap,which breaks the Doppler cooling limit and approaches half of the photon-recoil *** essential mechanism of cooling results is that the natural linewidth is comparable to the recoil frequency in such a 2S→3P ultraviolet narrow *** frequency stability is important in the cooling process,and thus,the UV laser was locked to an optical frequency comb referenced to an ultrastable optical *** cooling was numerically simulated to explain the cooling *** results can provide an ideal platform in the field of precision measurements and ultracold Fermi gases.

关键词： cold atom narrow-line UV cooling photon-recoil limit

Effect of Carbon Addition on Microstructure and Properties of WC-Co Cemented Carbides

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Journal of Materials Science & Technology 2012年第9期28卷 837-843页

作者： Chongbin Wei Xiaoyan Song Jun Fu Xiaosen Lv Haibin Wang Yang Cao ShixianZhao xuemei liu College of Materials Science and Engineering Key Lab of Advanced Functional MaterialsEducation Ministry of ChinaBeijing University of TechnologyBeijing 100124China Beijing Belying Hardalloy Co. Ltd.Beijing 100055China

Based on a unique method to synthesize WC-Co composite powder by in-situ reactions of metal oxides and carbon, the effects of the carbon addition in the initial powders on the phase constitution, microstructure and mechanical properties of the cemented carbides were investigated. It is found that with a suitable carbon addition the pure phase constitution can be obtained in the sintered bulk from the composite powder. The mechanical properties of the cemented carbides depend on the phase constitution and the WC grain structure. To obtain the excellent properties of the WC-Co bulk, it is important to obtain the pure phase constitution from the appropriate carbon addition in the initial powders and a suitable grain size.

关键词： Cemented carbides Carbon addition Composite powder Phase constitution Mechanical property

Characterization of glutamatergic VTA neural population responses to aversive and rewarding conditioning in freely-moving mice

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Science Bulletin 2019年第16期64卷 1167-1178页

作者： Quentin Montardy Zheng Zhou Zhuogui Lei xuemei liu Pengyu Zeng Chen Chen Yuanming liu Paula Sanz-Leon Kang Huang Liping Wang Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science Guangdong Provincial Key Laboratory of Brain Connectome and BehaviorCAS Center for Excellence in Brain Science and Intelligence TechnologyThe Brain Cognition and Brain Disease Institute(BCBDI)Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research InstitutionsShenzhen 518055China University of Chinese Academy of Sciences Beijing 100049China School of Physics the University of SydneySydney 2006Australia Centre for Integrative Brain Function the University of SydneySydney 2006Australia Department of Biomedical Sciences City University of Hong KongTat Chee AvenueKowloonHong KongSAR 999077China

The Ventral Tegmental Area(VTA) is a midbrain structure known to integrate aversive and rewarding stimuli, but little is known about the role of VTA glutamatergic(VGluT2) neurons in these *** activation of VGluT2 soma evokes rewarding behaviors, while activation of their downstream projections evokes aversive behaviors. To facilitate our understanding of these conflicting properties, we recorded calcium signals from VTAVGluT2+ neurons using fiber photometry in VGluT2-cre mice to investigate how this population was recruited by aversive and rewarding stimulation, both during unconditioned and conditioned protocols. Our results revealed that, as a population, VTAVGluT2+neurons responded similarly to unconditioned-aversive and unconditioned-rewarding stimulation. During aversive and rewarding conditioning, the CS-evoked responses gradually increased across trials whilst the US-evoked response remained stable. Retrieval 24 h after conditioning, during which mice received only CS presentation, resulted in VTAVGluT2+ neurons strongly responding to CS presentation and to the expected-US but only for aversive conditioning. To help understand these differences based on VTAVGluT2+ neuronal networks, the inputs and outputs of VTAVGluT2+ neurons were investigated using Cholera Toxin B(CTB) and rabies virus. Based on our results, we propose that the divergent VTAVGluT2+ neuronal responses to aversion and reward conditioning may be partly due to the existence of VTAVGluT2+ subpopulations that are characterized by their connectivity.

关键词： Ventral Tegmental Area Aversion Reward Conditioning Behavior

Grain size effect on wear resistance of WC-Co cemented carbides under different tribological conditions

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Journal of Materials Science & Technology 2019年第11期35卷 2435-2446页

作者： Haibin Wang Mark Gee Qingfan Qiu Hannah Zhang xuemei liu Hongbo Nie Xiaoyan Song Zuoren Nie College of Materials Science and Engineering Key Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaBeijing University of TechnologyBeijing 100124China National Physical Laboratory Hampton RoadTeddingtonTW110LWUK Xiamen Tungsten Co. Ltd.Xiamen 361009China

The grain-size dependence of wear resistance of WC-Co cemented carbides(with mean WC grain sizes of 2.2μm,1.6μm,0.8μm and 0.4μm,respectively)was investigated under different tribological *** results showed that the grain size had opposite effects on wear resistance of the cemented carbides in dry sliding wear and microabrasion *** the former condition,with decrease of WC grain size hence the increase of hardness,plastic deformation,fracture,fragmentation and oxidation were all mitigated,leading to a drastic decrease in the wear *** the latter condition,pull-out of WC grains after Co removal dominated the wear,so that the hardness of cemented carbide was not a core *** a result,the wear resistance of the cemented carbide generally showed a decreasing trend with decrease of the grain size,except for a slight increase in the ultrafine-grained cemented ***-pass scratching of the cemented carbides under various loads indicated the same failure mechanism as that in the sliding wear ***,the reasons for severe surface oxidation of the coarse-grained cemented carbides were disclosed.

关键词： Cemented carbide Grain size Fracture Surface oxidation Grain pull-out Wear resistance

Spectrum Allocation for Hierarchical Communication Networks in Smart Grid 36

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Spectrum Allocation for Hierarchical Communication Networks ...

Activation of parvalbumin interneurons in anterior cingulate cortex impairs observational fear

第36届中国控制会议

作者： MA Kai liu Pei liu xuemei YANG Jie liu Zhixin WEI Xiaomin School of Electrical Engineering Yanshan University Key Laboratory of System Control and Information Processing Ministry of EducationShanghai Jiao Tong University

ISBN: (纸本)9781538629185

In this study,a spectrum allocation algorithm is proposed to reduce the cost and the packets loss rate in the communications between the utility company and the *** establish a cost model based on spectrum allocation in smart ***,the subbands are allocated to different data aggregator units（DAUs） according to the confidence level and the maximum cost *** maximum cost corresponding to the DAUs are provided by different utility *** results demonstrate that the spectrum allocation algorithm can reduce the packets loss rate and make the cost of the utility companies all below the maximum cost requirements.

关键词： Smart Grid Spectrum Allocation Subband Confidence Level Cost

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Science Bulletin 2018年第12期63卷 771-778页

作者： Chunran Zhou Zheng Zhou Yushui Han Zhuogui Lei Lei Li Quentin Montardy xuemei liu Fuqiang Xu Liping Wang Shenzhen Key Laboratory of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science.Guangdong Provincial Key Laboratory of Brain Connectome and Behavior CAS Center for Excellence in Brain Science and Intelligence TechnologyThe Brain Cognition and Brain Disease Institute(BCBDI).Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China University of Chinese Academy of Sciences Beijing 100049.China Southern Medical University Guangzhou 510168China Center for Brain Science Key Laboratory of Magnetic Resonance in Biological Systems and State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsWuhan institute of Physics and MathematicsCAS Center for Excellence in Brain Science and Intelligence TechnologyChinese Academy of SciencesWuhan 430071China

The ability to detect conspecific＇s distress is crucial for animal survival. In rodent models, observational fear （OF） occurs when one animal perceives another fear related negative emotions, which may model certain behaviors caused by witnessing traumatic experiences in humans. Anterior cingulate cortex （ACC） has been showed to play a crucial role in OF. However, cellular and neural circuit basis relating to ACC governing OF is poorly understood. Here, we used Designer Receptor Exclusively Activated by a Designer Drug （DREADD） system to investigate the cell type specific circuit mechanism of ACC in OF. Firstly, inhibitory hM4D （Gi） designer receptor together with clozapine N-oxide （CNO） injection was applied to inactivate ACC neurons in the observer mice. We found that, chemogenetic inhibition of ACC resulted in a decreased freezing response in the observer mice. Next, combining PV-ires-Cre mice and Cre-dependent DREADD system, we selectively targeted the ACC parvalbumin （PV） interneurons with the excitatory hM3D （Gq） designer receptor. Activation of ACC PV interneurons following CNO injection reduced freezing response in the observer mice, while had no effect on freezing response in the demon- strator mice. Finally, monosynaptic rabies retrograde tracing revealed that ACC PV interneurons receive inputs from the mediodorsal thalamic nucleus （MD） and the ventromedial thalamic nucleus （VM）, both known for their roles in OF. Taken together, these findings reveal that ACC activation is important for OF, during which PV interneurons in ACC play an important regulatory role. Abnormal function of ACC PV interneurons might contribute to the pathology of empathy- deficits related diseases, such as autism and schizoohrenia.

关键词： Observational fear learning Anterior cingulate cortex PV interneurons Empathy