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Predicting Nitrogen Status of Rice Using Multispectral Data at Canopy Scale

Pedosphere 2006年第1期16卷 108-117页

作者： ZHANG Jin-Heng wang Ke J. S. BAILEY wang ren-chao College of Material and Environmental Science Qingdao University of Science and Technology Qingdao 266042（China）. Institute of Agricultural Remote Sensing＆Information System Application Zhejiang University Hangzhou 310029（China） Department of Agriculture and Rural Development for Northern Ireland Agricultural and Environmental Science Division gewforge Lane Belfast BT9 5PX （UK）

Two field experiments were conducted in Jiashan and Yuhang towns of Zhejiang Province, China, to study the feasibility of predicting N status of rice using canopy spectral reflectance. The canopy spectral reflectance of rice grown with different levels of N inputs was determined at several important growth stages. Statistical analyses showed that as a result of the different levels of N supply, there were significant differences in the N concentrations of canopy leaves at different growth stages. Since spectral reflectance measurements showed that the N status of rice was related to reflectance in the visible and NIR (near-infrared) ranges, observations for rice in 1 nm bandwidths were then converted to bandwidths in the visible and NIR spectral regions with IKONOS (space imaging) bandwidths and vegetation indices being used to predict the N status of rice. The results indicated that canopy reflectance measurements converted to ratio vegetation index (RVI) and normalized difference vegetation index (NDVI) for simulated IKONOS bands provided a better prediction of rice N status than the reflectance measurements in the simulated IKONOS bands themselves. The precision of the developed regression models using RVI and NDVI proved to be very high with R2 ranging from 0.82 to 0.94, and when validated with experimental data from a different site, the results were satisfactory with R2 ranging from 0.55 to 0.70. Thus, the results showed that theoretically it should be possible to monitor N status using remotely sensed data.

关键词： canopy spectral reflectance, multispectral data, nitrogen status rice vegetation indices

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Comparison Between Radial Basis Function Neural Network and Regression Model for Estimation of Rice Biophysical Parameters Using Remote Sensing

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Pedosphere 2009年第2期19卷 176-188页

作者： YANG Xiao-Hua wang Fu-Min HUANG Jing-Feng wang Jian-Wen wang ren-chao SHEN Zhang-Quan wang Xiu-Zhen Institute of Agricultural Remote Sensing ＆ Information Application Zhejiang University Hangzhou 310029 China Meteorological and Hydrographic Department of General Staff Headquarters Beijing 100081 China Zhejiang Meteorological Institute Hangzhou 310004 China

The radial basis function （RBF） emerged as a variant of artificial neural network. Generalized regression neural network （GRNN） is one type of RBF, and its principal advantages are that it can quickly learn and rapidly converge to the optimal regression surface with large number of data sets. Hyperspectral reflectance （350 to 2500 nm） data were recorded at two different rice sites in two experiment fields with two cultivars, three nitrogen treatments and one plant density （45 plants m^-2）. Stepwise multivariable regression model （SMR） and RBF were used to compare their predictability for the leaf area index （LAI） and green leaf chlorophyll density （GLCD） of rice based on reflectance （R） and its three different transformations, the first derivative reflectance （D1）, the second derivative reflectance （D2） and the log-transformed reflectance （LOG）. GRNN based on D1 was the best model for the prediction of rice LAI and CLCD. The relationships between different transformations of reflectance and rice parameters could be further improved when RBF was employed. Owing to its strong capacity for nonlinear mapping and good robustness, GRNN could maximize the sensitivity to chlorophyll content using D1. It is concluded that RBF may provide a useful exploratory and predictive tool for the estimation of rice biophysical parameters.

关键词： biophysical parameters radial basis function regression model remote sensing rice

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Quantifying Land Use Change in Zhejiang Coastal Region,China Using Multi-Temporal Landsat TM/ETM+Images

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Pedosphere 2007年第6期17卷 712-720页

作者： DING Han wang ren-chao WU Jia-Ping ZHOU Bin SHI Zhou DING Li-Xia Institute of Agricultural Remote Sensing and Information System Zhejiang University Hangzhou 310029 （China） Zhejiang Institute of Land Survey and Planning Hangzhou 310007 （China）

Landsat Thematic Mapper （TM） and Enhanced Thematic Mapper Plus （ETM＋） images in 1985, 1986, 1993, 1994 and 2001 were used to quantify the land use and land cover changes （LUCC） in the Zhejiang coastal region with a stratified unsupervised classification technique in conjunction with visual interpretation and to attempt an identification of the socioeconomic driving forces. In level I an overall accurate classification was achieved using a modified Anderson＇s Ⅰ/Ⅱ/Ⅲ-level classification scheme. The overall accuracy of the land use classification at Anderson level Ⅰ were 89.7% （1985）, 91.6% （1993）, and 90.4% （2001）. The most rapid land use change was a dramatic increase in urban or built-up areas, which quadrupled from 1985 to 2001. Over 90% of this newly expanded built-up area was originally paddy fields or other croplands. In different parts of the Zhejiang coastal region, urban land expansion was spatially uneven. Temporally, land use development did not stabilized, and the two study periods of time （1985-1993 and 1993-2001） had different transition styles. Socioeconomic factors, such as gross domestic product, total population, and financial expenditure, were all highly correlated with the expansion of urban or built-up areas. Based on the degree of urban sprawl and socioeconomic factors, cities and towns were further divided into six subgroups, which may help decision makers improve land use for the region.

关键词： coastal region driving factors land use change urban sprawl

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Thioacetamide Additive Homogenizing Zn Deposition Revealed by In Situ Digital Holography for Advanced Zn Ion Batteries

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Nano-Micro Letters 2024年第6期16卷 261-275页

作者： Kaixin ren Min Li Qinghong wang Baohua Liu Chuang Sun Boyu Yuan chao Lai Lifang Jiao chao wang School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhou 221116JiangsuPeople’s Republic of China Jiangsu Key Laboratory of Advanced Laser Materials and Devices School ofPhysics and Electronic EngineeringJiangsu Normal UniversityXuzhou 221116JiangsuPeople’s Republic of China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai University300071 TianjinPeople’s Republic of China

Zinc ion batteries are considered as potential energy storage devices due to their advantages of low-cost,high-safety,and high theoretical ***,dendrite growth and chemical corrosion occurring on Zn anode limit their *** problems can be tackled through the optimization of the ***,the screening of electrolyte additives using normal electrochemical methods is time-consuming and ***,a fast and simple method based on the digital holography is *** can realize the in situ monitoring of electrode/electrolyte interface and provide direct information concerning ion concentration evolution of the diffusion *** is effective and time-saving in estimating the homogeneity of the deposition layer and predicting the tendency of dendrite growth,thus able to value the applicability of electrolyte *** feasibility of this method is further validated by the forecast and evaluation of thioacetamide *** on systematic characterization,it is proved that the introduction of thioacetamide can not only regulate the interficial ion flux to induce dendrite-free Zn deposition,but also construct adsorption molecule layers to inhibit side reactions of Zn *** easy to operate,capable of in situ observation,and able to endure harsh conditions,digital holography method will be a promising approach for the interfacial investigation of other battery systems.

关键词： Digital holographic microscopy In situ observation Electrode/electrolyte interface Zn dendrites Screening electrolyte additives

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Numerical simulation and experimental research of surrounding rock deformation of floor roadway under short-distance coal seam group combined mining

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Journal of Coal Science & Engineering(China) 2010年第3期16卷 230-234页

作者： LIAN Zhen-shan wang Ji-ren HAO chao-yu Research Institute of Safety Technology Liaoning Technical University Fuxin 123000 China

According to the influence of the combination of short-distance coal seam group on mining roadway, using numerical simulation software FLAG2D to draw the abutment pressure distribution ahead the working face and the area of influence in fully-mechanized mining conditions, the variation rules of surrounding rock supporting pressure of floor roadway and the deformation rules were summarized. GYS-300 anchor dynamometer was used to measure the roadway surface displacement, and the conclusions of numerical simulation were verified.

关键词： short-distance coal seam group abutment pressure numerical simulation distortion rules of roadway FLAC2D

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Complete Genome Sequence of Mycoplasma ovipneumoniae Strain NM2010, Which Was Isolated from a Sheep in China

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Journal of Integrative Agriculture 2014年第11期13卷 2562-2563页

作者： wang Xiao-hui HUANG Hai-bi CHENG Chen wang ren-chao ZHENG Jia-qi HAO Yongqing ZHANG Wen-guang Key Laboratory of Microbiology & Immunology College of Veterinary Medicine Inner Mongolia Agricultural University College of Animal Science Inner Mongolia Agricultural University

Mycoplasma ovipneumoniae, a kind of mycoplasma bacteria, commonly infects the respiratory tract causing respiratory disease in sheep and goats worldwide. Here, the complete genome sequence of M. ovipneumoniae strain N... 详细信息

关键词： Mycoplasma ovipneumoniae strain NM2010 complete genome sequence sheep

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Nickel-Catalyzed Stereoselective Migratory Carboboration of 1,4-Cyclohexadiene

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Chinese Journal of Chemistry 2024年第4期42卷 356-362页

作者： Yaoyu ren Lujin wang chao Ding Yangyang Li Guoyin Yin The Institute for Advanced Studies Wuhan UniversityWuhanHubei430072 China

Multi-substituted cyclohexanes play a crucial role as scaffolds in bioactive *** significant progress has been made in synthesizing substituted cyclohexanes,methods for the stereoselective assembly of 1,3-disubstituted cyclohexanes remain *** study presents a novel approach involving nickel catalysis to achieve stereoselective carboboration of 1,*** innovative process allows for the simultaneous introduction of a boron group and an aryl or an alkyl fragment into the 1,4-cyclohexadiene framework under mild conditions,with exclusive regioselectivity and excellent cis *** resulting products feature a double carbon bond and the incorporation of the boron group,offering significant potential for subsequent transformations and downstream applications.

关键词： 1,4-Cyclohexadiene Carboboration Nickel Chain-walking Stereoselectivity Difunctionalization

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Deformation mechanism and collapse treatment of the rock surrounding a shallow tunnel based on on-site monitoring

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Journal of Mountain Science 2020年第12期17卷 2897-2914页

作者： QIU Hong-zhi CHEN Xiao-qing WU Qi-hong wang ren-chao ZHAO Wan-yu QIAN Ke-jiang School of Architecture and Civil Engineering Chengdu UniversityChengdu 610106China Key Laboratory of Mountain Hazards and Earth Surface Processes Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China Hunan International Scientific and Technological Innovation Cooperation Base of Advanced Construction and Maintenance Technology of Highway Changsha University of Science&TechnologyChangsha 410114China School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

When tunnels are constructed at shallow depths in areas with poor geological conditions,such as portal sections,valleys and hillsides in regions with granitic bedrock,considerable excavation-induced deformation of the surrounding rock may occur,potentially resulting in tunnel *** main reason for these problems is the lack of understanding of the deformation mechanism and evolution of the soft granitic rock surrounding the tunnel and the adoption of inappropriate construction technology and *** article analyzes the deformation mechanism of the rock surrounding a shallow tunnel based on in situ monitoring data as a case study and suggests that certain measures should be taken to effectively control the deformation of the surrounding rock and to minimize the potential for tunnel *** results show that the deformation of the granitic soil surrounding the tunnel can be divided into three stages:the rapid deformation stage,the slow deformation stage and the stabilization *** construction methods should be carefully selected to ensure safety during tunnel excavation in the first *** avoid secondary disasters caused by tunnel collapses,three treatment measures may be implemented as part of safety management:enhancing the monitoring of the surrounding rock deformation,adjusting the construction methods and optimizing the support *** particular,accurate monitoring data and timely information feedback play a vital role in tunnel ***,engineers with considerable engineering experience and professional knowledge are needed to analyze the monitoring data and make accurate predictions of tunnel deformation to ensure that reasonable measures are taken in the process of shallow tunnel excavation.

关键词： Shallow tunnel Surrounding rock deformation Field monitoring Treatment for collapse Information feedback

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Laparoscopic resection of synchronous intraductal papillary mucinous neoplasms:A case report

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World Journal of Gastroenterology 2012年第44期18卷 6510-6514页

作者： Xiao-Wu Xu Rong-Hua Li Wei Zhou Jie wang ren-chao Zhang Ke Chen Yi-Ping Mou Department of General Surgery Sir Run Run Shaw Hospital School of Medicine Zhejiang Uni- versity Hangzhou 310016 Zhejiang Province China

We describe herein a 68-year-old woman who was diagnosed with a quite rare entity of intraductal papillary mucinous neoplasms(IPMNs) occurring simultaneously in the left lateral lobe of liver and the tail of *** computed tomography and magnetic resonance cholangiopancreatography showed a cystic dilatation of the pancreatic duct in the pancreatic tail,which suggested an IPMN,and multiple intrahepatic duct stones in the left lateral *** patient underwent a laparoscopic left lateral hepatolobectomy and spleenpreserving distal ***-operative finding of massive mucin in the dilated bile duct implied an intraductal mucinous tumor in the *** diagnosis of synchronous IPMNs in the liver and pancreas was confirmed by pathological *** patient was followed up for 6 mo without signs of *** several cases of IPMN of liver without any pancreatic association have been reported,the simultaneous occurrence of IPMNs in the liver and pancreas is very *** the best of our knowledge,it is the first reported case treated by laparoscopic resection.

关键词： Laparoscopy Pancreas Liver Intraductalpapillary mucinous neoplasm Synchronous neoplasm

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A data-driven approach for predicting the fatigue life and failure mode of self-piercing rivet joints

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Advances in Manufacturing 2024年第3期12卷 538-555页

作者： Jian wang Qiu-ren Chen Li Huang Chen-Di Wei chao Tong Xian-Hui wang Qing Liu Nanjing University of Science and Technology Nanjing210094People’s Republic of China Material Academy JitriSuzhou215100JiangsuPeople’s Republic of China Key Laboratory for Light-weight Materials Nanjing Tech UniversityNanjing210009People’s Republic of China Xi’an Jiaotong-Liverpool University Suzhou215123JiangsuPeople’s Republic of China

In lightweight automotive vehicles,the application of self-piercing rivet(SPR)joints is becoming increasingly *** the importance of automotive service performance,the fatigue performance of SPR joints has received considerable ***,this study proposes a data-driven approach to predict the fatigue life and failure modes of SPR *** dataset comprises three specimen types:cross-tensile,cross-peel,and *** ensure data consistency,a finite element analysis was employed to convert the external loads of the different *** selection was implemented using various machine-learning algorithms to determine the model *** Gaussian process regression algorithm was used to predict fatigue life,and its performance was compared with different kernel functions commonly used in the *** results revealed that the Matern kernel exhibited an exceptional predictive capability for fatigue *** the data points,95.9%fell within the 3-fold error band,and the remaining 4.1%exceeded the 3-fold error band owing to inherent dispersion in the fatigue *** predict the failure location,various tree and artificial neural network(ANN)models were *** findings indicated that the ANN models slightly outperformed the tree *** ANN model accurately predicts the failure of joints with varying dimensions and ***,minor deviations were observed for the joints with the same ***,this data-driven approach provided a reliable predictive model for estimating the fatigue life and failure location of SPR joints.

关键词： Self-piercing rivet(SPR)joints Fatigue life prediction Failure mode prediction Machine learning

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