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Mapping winter wheat using phenological feature of peak before winter on the North China Plain based on time-series MODIS data

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Journal of Integrative Agriculture 2017年第2期16卷 348-359页

作者： TAO Jian-bin WU Wen-bin ZHOU Yong WANG Yu jianG Yan Key Laboratory of Agri-informatics Ministry of Agriculture/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences Key Laboratory for Geographical Process Analysis & Simulation of Hubei Province/School of Urban and Environmental Sciences Central China Normal University

By employing the unique phenological feature of winter wheat extracted from peak before winter （PBW） and the advantages of moderate resolution imaging spectroradiometer （MODIS） data with high temporal resolution and intermediate spatial resolution, a remote sensing-based model for mapping winter wheat on the North China Plain was built through integration with Landsat images and land-use data. First, a phenological window, PBW was drawn from time-series MODIS data. Next, feature extraction was performed for the PBW to reduce feature dimension and enhance its information. Finally, a regression model was built to model the relationship of the phenological feature and the sample data. The amount of information of the PBW was evaluated and compared with that of the main peak （MP）. The relative precision of the mapping reached up to 92% in comparison to the Landsat sample data, and ranged between 87 and 96% in comparison to the statistical data. These results were sufficient to satisfy the accuracy requirements for winter wheat mapping at a large scale. Moreover, the proposed method has the ability to obtain the distribution information for winter wheat in an earlier period than previous studies. This study could throw light on the monitoring of winter wheat in China by using unique phenological feature of winter wheat.

关键词： time-series MODIS data phenological feature peak before wintering winter wheat mapping

Fusing multi-source data to map spatio-temporal dynamics of winter rape on the jianghan Plain and Dongting Lake Plain, China

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Journal of Integrative Agriculture 2019年第10期18卷 2393-2407页

作者： TAO Jian-bin LIU Wen-bin TAN Wen-xia KONG Xiang-bing XU Meng Key Laboratory for Geographical Process Analysis & Simulation of Hubei Province/School of Urban and Environmental Sciences Central China Normal UniversityWuhan 430079P.R.China Key Laboratory of the Loess Plateau Soil Erosion and Water Loss Process and Control Ministry of Water Resources/Yellow River Institute of Hydraulic ResearchZhengzhou 450003P.R.China

Mapping crop distribution with remote sensing data is of great importance for agricultural production, food security and agricultural sustainability. Winter rape is an important oil crop, which plays an important role in the cooking oil market of China. The jianghan Plain and Dongting Lake Plain (JPDLP) are major agricultural production areas in China. Essential changes in winter rape distribution have taken place in this area during the 21st century. However, the pattern of these changes remains unknown. In this study, the spatial and temporal dynamics of winter rape from 2000 to 2017 on the JPDLP were analyzed. An artificial neural network (ANN)-based classification method was proposed to map fractional winter rape distribution by fusing moderate resolution imaging spectrometer (MODIS) data and high-resolution imagery. The results are as follows:(1) The total winter rape acreages on the JPDLP dropped significantly, especially on the jianghan Plain with a decline of about 45% during 2000 and 2017.(2) The winter rape abundance keeps changing with about 20–30% croplands changing their abundance drastically in every two consecutive observation years.(3) The winter rape has obvious regional differentiation for the trend of its change at the county level, and the decreasing trend was observed more strongly in the traditionally dominant agricultural counties.

关键词： winter rape,spatio-temporal dynamics,time-series MODIS data artificial neural network

Learning long-term temporal contexts using skip RNN for continuous emotion recognition

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Virtual Reality & Intelligent Hardware 2021年第1期3卷 55-64页

作者： jian HUANG bin LIU jianhua tao National Laboratory of Pattern Recognition Institute of AutomationChinese Academy of SciencesBeijing 100049China CAS Center for Excellence in Brain Science and Intelligence Technology Beijing 100049China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China

Background Continuous emotion recognition as a function of time assigns emotional values to every frame in a sequence.Incorporating long-term temporal context information is essential for continuous emotion recognition tasks.Methods For this purpose,we employ a window of feature frames in place of a single frame as inputs to strengthen the temporal modeling at the feature level.The ideas of frame skipping and temporal pooling are utilized to alleviate the resulting redundancy.At the model level,we leverage the skip recurrent neural network to model the long-term temporal variability by skipping trivial information for continuous emotion recognition.Results The experimental results using the AVEC 2017 database demonstrate that our proposed methods are beneficial to a performance improvement.Further,the skip long short-term memory(LSTM)model can focus on the critical emotional state when training the models,thereby achieving a better performance than the LSTM model and other methods.

关键词： Continuous emotion recognition Skip RNN Temporal contexts Redundancy

Call for Papers:Special Section on Progress of Analysis Techniques for Domain-Specific Big Data

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Journal of Electronic Science and Technology 2023年第2期21卷 95-96页

作者： Ling Tian jian-Hua tao bin Zhou University of Electronic Science and Technology of China Tsinghua University National University of Defense Technology

Since the concept of“Big Data”was first introduced in Nature in 2008,it has been widely applied in fields,such as business,healthcare,national defense,education,transportation,and security.With the maturity of artificial intelligence technology,big data analysis techniques tailored to various fields have made significant progress,but still face many challenges in terms of data quality,algorithms,and computing power.

关键词： artificial Big computing

OXCT1 regulates NF-κB signaling pathway through β-hydroxybutyrate-mediated ketone body homeostasis in lung cancer

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Genes & Diseases 2023年第2期10卷 352-355页

作者： Zhuo Lu Tianyu Han tao Wang Mingxi Gan Caifeng Xie Bentong Yu jian-bin Wang College of Life Science Nanchang UniversityNanchangJiangxi 330031China School of Basic Medical Sciences Nanchang UniversityNanchangJiangxi 330031China jiangxi Institute of Respiratory Disease The First Affiliated Hospital of Nanchang UniversityNanchangJiangxi 330006China Department of Thoracic Surgery The First Affiliated Hospital of Nanchang UniversityNanchangJiangxi 330006China

Metabolic reprogramming is one of the hallmarks of cancer.1 Ketone bodies behave as alternative fuel for cancer cells to support survival and proliferation.2 3-Oxoacid CoA-transferase 1 (OXCT1) is a key enzyme that catalyzes the first and rate-limiting step of ketolysis. Recently, several studies have revealed the significance of OXCT1 in cancer development, though the underlying mechanisms remain largely unknown.3 In this study, we revealed a novel regulatory mechanism for tumorigenesis that OXCT1 regulated SREBP1-TRIM21-p65 axis through ketone body homeostasis in non-small cell lung cancer (NSCLC). In terms of mechanism, we found that OXCT1 could activate NF-κB signaling pathway by suppressing transcriptional activity of the sterol regulatory element binding protein 1 (SREBP1). As a transcription factor, SREBP1 could bind to the promoter of E3 ubiquitin ligase TRIM21, which mediated the ubiquitination of p65. Furthermore, we demonstrated that OXCT1 could maintain the homeostasis of β-hydroxybutyrate (β-HB), which acted as a signaling metabolite to activate SREBP1. Thus, β-HB connected OXCT1 with SREBP1 to activate NF-κB signaling pathway and promoted tumor initiation and progression. Taken together, these findings highlight a previously unappreciated mechanism for activation of NF-κB signaling by OXCT1 and ketone body, and demonstrate that targeting OXCT1 can inhibit NSCLC tumorigenesis.

关键词： homeostasis lung ketone

Effect of surface Cr/C infiltration on microstructure,mechanical properties and wear resistance of high chromium cast iron

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China Foundry 2022年第3期19卷 218-224页

作者： Peng Chen Zhao-yang Wu Yan-liang Yi jian-bin Huang tao Shang Wei Li Institute of Advance Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou 510632China Shaoguan Research Institute of Jinan University Shaoguan 512027GuangdongChina Ningxia Tiandi Heavy Equipment Technology Co. Ltd.Yinchuan 753001NingxiaChina

A new type of high chromium cast iron(HCCI)was prepared,and its microstructure,mechanical properties,and abrasion resistance were investigated systematically.Results showed that after surface carburizing and chromizing,the microstructure of HCCI mainly consists of martensite,boride(M_(2)B),and carbide(M_(7)C_(3)),accompanied with a large amount of secondary precipitations M_(23)C_(6).Moreover,the morphology and hardness of the carbide and boride in HCCI change little,while the volume fraction of carbide and boride increases from 16.23%to 23.16%.This effectively increases the surface hardness of HCCI from 64.53±0.50 HRC to 66.58±0.50 HRC,with the result that the surface of HCCI possesses a better abrasion resistance compared to the center position.Furthermore,the wear mechanism of HCCI changes from micro-plowing to micro-cutting with the increase of surface hardness.

关键词： high chromium cast iron carburizing and chromizing mechanical property abrasion resistance

Design and motion analysis of reconfigurable wheel-legged mobile robot

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Defence Technology（防务技术） 2022年第6期18卷 1023-1040页

作者： Shuo Zhang jian-tao Yao Ying-bin Wang Zi-sheng Liu Yun-dou Xu Yong-sheng Zhao School of Mechanical Engineering Yanshan UniversityHebeiChina

An adaptive wheel-legged shape reconfigurable mobile robot,based on a scissor-like mechanism,is proposed for an obstacle detecting and surmounting robot,moving on complex terrain.The robot can dynamically adjust its own shape,according to the environment,realizing a transformation of wheel shape into leg shape and vice versa.Each wheel-legged mechanism has one degree of freedom,which means that only the relative motion of the inner and outer discs is needed to achieve the transformation of the shape into a wheel or a leg.First,the force analysis of the conversion process of the wheel-legged mechanism is carried out,while the relationship between the driving torque and the friction factor in the non-conversion trigger stage and in the conversion trigger stage is obtained.The results showed that the shape conversion can be better realized by increasing the friction factor of the trigger point.Next,the kinematics analysis of the robot,including climbing the obstacles,stairs and gully,is carried out.The motion of the spokes tip is obtained,in order to derive the folding ratio and the surmountable obstacle height of the wheel-legged mechanism.The parameters of the wheel-legged structure are optimized,to obtain better stability and obstacle climbing ability.Finally,a dynamic simulation model is established by ADAMS,to verify the obstacle climbing performance and gait rationality of the robot,in addition to a prototype experiment.The results showed that the surmountable obstacle height of the robot is about3.05 times the spoke radius.The robot has the stability of a traditional wheel mechanism and the obstacle surmount performance of a leg mechanism,making it more suitable for field reconnaissance and exploration missions.

关键词： Mobile robots Scissor mechanism Kinematics ADAMS simulation Obstacle surmounting

Recent advances in breathable electronics

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Nano Research 2023年第3期16卷 4130-4142页

作者： Zhuocheng Yan jian Xiong bin Wang Min Gao Guangqiang Yin tao Hu Taisong Pan Xinzhong Wang Yuan Lin Department of Electronic Communication and Technology Shenzhen Institute of Information TechnologyShenzhen 518172China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 610054China School of Information and Software Engineering University of Electronic Science and Technology of ChinaChengdu 610054China Engineering Cooperation on Applied Medicine Research Center University of Electronic Science and Technology of ChinaChengdu 610054China

The successful implementation of bioelectronic devices attached to living organism hinges on a number of material and device characteristics,including not only electrical and mechanical performances to gather physiological signals from living organism thus enabling status monitoring,but also permeability or breathability for gas/nutrient exchange between living organisms and surroundings to ensure minimum perturbation of the intrinsic biological function.However,most bioelectronic devices built on planar polymeric substrates,such as polydimethylsiloxane(PDMS),polyurethane(PU),and polyimide(PI),lack efficient gas permeability,which may hinder the emission of volatile compounds from the surface of living organism,affecting the natural metabolism and reducing the comfort of wearing.Thus,achieving permeability or breathability in bioelectronic devices is a significant challenge.Currently,the devices made of gas-permeable materials with porous structures,that combine electronic components with daily garments,such as fibric and textile,offer exciting opportunities for breathable electronics.In this review,several types of gas-permeable materials with their synthesis and processing routes are outlines.Then,two methods for measuring water vapor transmission rate of materials are discussed in depth.Finally,recent progress in the use of gaspermeable materials for the applications of plant-and skin-attached electronics is summarized systematically.

关键词： breathability gas permeability porous sponge foam nano materials plant electronics wearable electronics

Research progress on advanced rail materials for electromagnetic railgun technology

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Defence Technology（防务技术） 2021年第2期17卷 429-439页

作者： Hong-bin Xie Hui-ya Yang jian Yu Ming-yu Gao jian-dong Shou You-tong Fang Jia-bin Liu Hong-tao Wang School of Materials Science and Engineering Zhejiang UniversityHangzhou310027China Center for X-mechanics Faculty of EngineeringZhejiang UniversityHangzhou310027China

Electromagnetic railgun attracts more and more attention due to its advantage in speed,cost,and obscurity.It is found that the rail should withstand huge mechanical and thermal shocks during the launching operation.The forms of rail failure are accompanied by gouge,grooving,transition,and arc ablation,etc.The service life of the rail has become a bottleneck restricting the development of electromagnetic railgun technology.A series of researches are carried out to solve rail failure,including analysing the failure mechanism and using various advanced rail materials.This paper provides a comprehensive review of rail materials,including material composition,preparation,microstructure,and properties.We begin from a short background of the requirement of the rail material.Then a detailed investigation of rail materials is described,and the performances of those materials are introduced.Finally,further development prospect of rail material is discussed.

关键词： Strength Conductivity Electromagnetic railgun Copper alloys Rai