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Multi-year monitoring of paddy rice planting area in Northeast China using MODIS time series data

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第10期14卷 934-946页

作者： jing-jing shi jing-feng HUANG Feng ZHANG Institute of Agricultural Remote Sensing and Information Application Zhejiang University Key Laboratory of Agricultural Remote Sensing and Information System of Zhejiang Province Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health Zhejiang University

e The objective of this study was to investigate the tempo-spatial distribution of paddy rice in Northeast China using moderate resolution imaging spectroradiometer （MODIS） data. We developed an algorithm for detection and estimation of the transplanting and flooding periods of paddy rice with a combination of enhanced vegetation index （EVI） and land surface water index with a central wavelength at 2130 nm （LSW12130）. In two intensive sites in Northeast China, fine resolution satellite imagery was used to validate the performance of the algorithm at pixel and 3x3 pixel window levels, respectively. The commission and omission errors in both of the intensive sites were approximately less than 20%. Based on the algorithm, annual distribution of paddy rice in Northeast China from 2001 to 2009 was mapped and analyzed. The results demonstrated that the MODIS-derived area was highly correlated with published agricultural statistical data with a coefficient of determination （R^2） value of 0.847. It also revealed a sharp decline in 2003, especially in the Sanjiang Plain located in the northeast of Heilongjiang Province, due to the oversupply and price decline of rice in 2002. These results suggest that the approaches are available for accurate and reliable monitoring of rice cultivated areas and variation on a large scale.

关键词： Paddy rice Moderate resolution imaging spectroradiometer(MODIS) Northeast China Enhanced vegetation index Land surface water index

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Discrimination of rice panicles by hyperspectral reflectance data based on principal component analysis and support vector classification

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第1期11卷 71-78页

作者： Zhan-yu LIU jing-jing shi Li-wen ZHANG jing-feng HUANG Institute of Agricultural Remote Sensing and Information System Application Zhejiang University Hangzhou 310029 China Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health Zhejiang University Hangzhon 310029 China Key Laboratory of Agricultural Remote Sensing and lnformation System in Zhejiang Province Hangzhou 310029 China

Detection of crop health conditions plays an important role in making control strategies of crop disease and insect damage and gaining high-quality production at late growth stages. In this study, hyperspectral reflectance of rice panicles was measured at the visible and near-infrared regions. The panicles were divided into three groups according to health conditions： healthy panicles, empty panicles caused by Nilaparvata lugens St^l, and panicles infected with Ustilaginoidea virens. Low order derivative spectra, namely, the first and second orders, were obtained using different techniques. Principal component analysis （PCA） was performed to obtain the principal component spectra （PCS） of the foregoing derivative and raw spectra to reduce the reflectance spectral dimension. Support vector classification （SVC） was employed to discriminate the healthy, empty, and infected panicles, with the front three PCS as the in- dependent variables. The overall accuracy and kappa coefficient were used to assess the classification accuracy of SVC. The overall accuracies of SVC with PCS derived from the raw, first, and second reflectance spectra for the testing dataset were 96.55%, 99.14%, and 96.55%, and the kappa coefficients were 94.81%, 98.71%, and 94.82%, respectively. Our results demonstrated that it is feasible to use visible and near-infrared spectroscopy to discriminate health conditions of rice panicles.

关键词： Rice panicle Principal component analysis (PCA) Support vector classification (SVC) Hyperspectra reflectance Derivative spectra

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Effects of Deformation Texture and Twins on the Corrosion Resistance of Rolled AZ31 Mg Alloy Under 5% Uniaxial Compression

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Acta Metallurgica Sinica(English Letters) 2017年第10期30卷 921-930页

作者： Chen Wang Hao Ding Bing-Shu Wang Kui Wang jing-jing shi Jun-Feng Chen College of Materials Science and Engineering Fuzhou University

The deformation texture and twin effect of rolled AZ31 Mg alloy on the corrosion resistance in simulated body fluid（SBF） at room temperature were examined by potentiodynamic polarization and electrochemical impedance *** corrosion morphology evolution after being immersed in SBF for 24 h has been analyzed by scanning electron microscope. The results show that the inhomogeneous deformation leaded to the obvious differences in the *** corrosion rate of rolled AZ31 Mg alloy decreased dramatically in the transverse direction（TD） plane, which mainly consisted of {0001} deformation texture, making TD plane be a lower surface energy,and thus a higher corrosion resistance, while the corrosion resistance of the plane with 45° to TD direction（45 TD plane） containing enormous{10-12} tension twins decreased after 5% uniaxial compression. The {10-12} tension twins accelerate the rate of corrosion procedure and pitting corrosion. Moreover, it is suggested that the deformation texture affects the corrosion behavior more than the twins do. This study indicates that the corrosion rate of AZ31 Mg alloy in SBF can be modified by the small uniaxial compression.

关键词： AZ31 Mg alloy Twins Texture Corrosion resistance

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An uncertainty investigation for liner impedance eduction methods

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Chinese Journal of Aeronautics 2024年第3期37卷 49-59页

作者： Weihao shi Xiaodong jing School of Energy and Power Engineering Beihang UniversityBeijing 100191China

Impedance eduction methods have been developed for decades to meet the increasing need for high-quality impedance data in the design and optimization of acoustic *** this end,it is important to fully investigate the uncertainty problem,to which only limited attention has been devoted so *** paper considers the possibility of acoustically-induced structural vibration as a nonnegligible uncertainty or error source in impedance eduction *** the frequency moves away from the resonant frequency,with the increase in the value of cavity reactance,the acoustic particle velocity inside liner orifices possibly decreases to the extent comparable to the vibration velocity of liner facing ***,the acoustically-induced vibration,although generally being weak except at the inherent structural frequencies,may considerably affect the impedance eduction results near the anti-resonant frequency where the liner has poor *** demonstrate the effect of structural vibration,the vibration velocity of liner facing sheet is estimated from the experimentally educed admittance of the liner samples whose orifices are sealed with ***,a three-dimensional numerical model is set up,in which normal particle velocity is introduced over the solid portion of liner facing sheet to imitate structural vibration,rather than directly solving the acoustic-structural coupling *** shown by the results,the vibration of liner facing sheet,whose velocity is as small as estimated by the experiment,can result in anomalous deviation of the educed impedance from the impedance model near the anti-resonant *** trend that the anomalous deviation varies with frequency is numerically captured.

关键词： Impedance eduction Uncertainty analysis Acoustically-induced structural vibration Anti-resonant frequency Perforated liner

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Langerhans cell histiocytosis misdiagnosed as thyroid malignancy: A case report

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World Journal of Clinical Cases 2023年第5期11卷 1152-1157页

作者： jing-jing shi You Peng Yu Zhang Li Zhou Gang Pan Department of Oncological Surgery Affiliated Hangzhou First People's HospitalZhejiang University School of MedicineHangzhou 310006Zhejiang ProvinceChina

BACKGROUND The incidence of Langerhans cell histiocytosis(LCH) is low, and involvement of the thyroid is even rarer, which results in high missed diagnosis or misdiagnosis *** SUMMARY We report a young woman with a thyroid nodule. Thyroid malignancy was suggested by fine needle aspiration, but she was eventually diagnosed with multisystem LCH, thus avoiding *** The clinical manifestations of LCH involving the thyroid are atypical, and the diagnosis depends on pathology. Surgery is the main method for treating primary thyroid LCH, while chemotherapy is the main treatment method for multisystem LCH.

关键词： Thyroid Langerhans cell histiocytosis Thyroidectomy Treatment Case report

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Hierarchical Privacy Protection Model in Advanced Metering Infrastructure Based on Cloud and Fog Assistance

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Computers, Materials & Continua 2024年第8期80卷 3193-3219页

作者： Linghong Kuang Wenlong shi jing Zhang School of Computer Science and Mathematics Fujian University of TechnologyFuzhou350118China Fujian Provincial Key Laboratory of Big Data Mining and Applications Fuzhou350118China

The Advanced Metering Infrastructure(AMI),as a crucial subsystem in the smart grid,is responsible for measuring user electricity consumption and plays a vital role in communication between providers and ***,with the advancement of information and communication technology,new security and privacy challenges have emerged for *** address these challenges and enhance the security and privacy of user data in the smart grid,a Hierarchical Privacy Protection Model in Advanced Metering Infrastructure based on Cloud and Fog Assistance(HPPM-AMICFA)is proposed in this *** proposed model integrates cloud and fog computing with hierarchical threshold encryption,offering a flexible and efficient privacy protection solution that significantly enhances data security in the smart *** methodology involves setting user protection levels by processing missing data and utilizing fuzzy comprehensive analysis to evaluate user importance,thereby assigning appropriate protection ***,a hierarchical threshold encryption algorithm is developed to provide differentiated protection strategies for fog nodes based on user IDs,ensuring secure aggregation and encryption of user *** results demonstrate that HPPM-AMICFA effectively resists various attack strategies while minimizing time costs,thereby safeguarding user data in the smart grid.

关键词： AMI cloud and fog assistance fuzzy comprehensive analysis hierarchical threshold encryption

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Synergistically constructed lamination-like network of redox-active polyimide and MXene via π-π interactions for aqueous NH_(4)^(+) storage

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Chinese Journal of Chemical Engineering 2024年第7期71卷 217-224页

作者： jing He Hongye Xuan jing Jin Ke Yu Changyao Liyang Lintong Hu Minjie shi Chao Yan School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Jiangsu New Yangzi shipbuilding Co. LtdJingjiang 214532China

As a nonmetallic charge carrier,ammonium ion(NH_(4)^(+))has garnered significant attention in the construction of aqueous batteries due to its advantages of low molar mass,small hydration size and rapid diffusion in aqueous *** are a kind of potential electro-active materials for aqueous NH_(4)^(+)***,traditional polymer electrodes are typically created by covering the bulky collectors with excessive additives,which could lead to low volume capacity and unsatisfactory ***,a nanoparticle-like polyimide(PI)was synthesized and then combined with MXene nanosheets to synergistically construct an additive-free and self-standing PI@MXene composite ***,the redox-active PI nanoparticles are enclosed between conductive MXene flakes to create a 3D lamination-like network that promotes electron transmission,while theπ-πinteractions existing between PI and MXene contribute to the enhanced structural integrity and stability within the composite *** such,it delivers superior aqueous NH_(4)^(+)storage behaviors in terms of a notable specific capacity of 110.7 mA·h·cm^(–3) and a long lifespan with only 0.0064%drop each ***,in-situ Raman and UV–Vis examinations provide evidence of reversible and stable redox mechanism of the PI@MXene composite electrode during NH_(4)^(+)uptake/removal,highlighting its significance in the area of electrochemical energy storage.

关键词： Synergetic coupling Composite materials Polyimide Energy storage Aqueous ammonium ion batteries

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Reoxidation of liquid steel and evolution of inclusions during protective atmosphere electroslag remelting of Ce-containing heat-resistant stainless steel

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Journal of Iron and Steel Research International 2024年第8期31卷 1923-1935页

作者： Yu Zhao Cheng-bin shi shijun Wang Peng Ren jing Li State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing(USTB)Beijing 100083China

The evolution of Ce-containing inclusions and its correlation with the reoxidation of liquid steel during protective atmosphere electroslag remelting(ESR)of heat-resistant steel were *** reoxidation of liquid steel took place during the ESR,resulting in the oxygen pickup from 0.0014 to 0.0053 wt.%.The inclusions in the consumable electrode,liquid metal pool and remelted ingot are Ce_(2)O_(2)S and Ce_(2)O,inclusions *** inclusions in the remelted ingot are originated from three ways:(I)the original inclusions from the electrode;(Il)the newly formed Ce_(2)O_(2)S and Ce_(2)O_(3) inclusions in the liquid metal pool by reoxidation remaining still in remelted ingot;(IlI)the newly generated Ce2O2S and Ce_(2)O_(3) inclusions during cooling and solidification of liquid *** relative proportions of Ce_(2)O_(3) inclusions in liquid metal pool and remelted ingot are 41% and 76.5%,*** inclusions ranging from 2 to 5μm in the remelted ingot take up 55%,followed by the inclusions smaller than 2μm(43%of total inclusions).The number proportion of the Ce_(2)0,inclusions in the liquid metal pool which were removed by floating up into slag is 1.96×10-5%.

关键词： Non-metallic inclusion Electroslag remelting Rare earth cerium Reoxidation Inclusion evolution

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Validation of Veterans Specific Activity Questionnaire to assess exercise tolerance of Chinese elderly with coronary heart disease

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Journal of Geriatric Cardiology 2016年第12期13卷 973-977页

作者： Yan WANG jing-jing shi Bo-Zhong WANG Department of Cardiac Rehabilitation Zhejiang Hospital Hangzhou Zhejiang China Department of Cardiology Cixi No.6 Peoples'HospitaL Cixi Zhejiang China

Objective The Veterans Specific Activity Questionnaire （VSAQ） has been used to assess exercise tolerance. Nevertheless, there is no val- idated Chinese version. The aim of this study is to determine whether a questionnaire-based method using the Chinese version of VSAQ （the modified VSAQ） is a practical tool to assess exercise tolerance of Chinese elderly with coronary heart disease. Methods One hundred thirty consecutive elderly patients who were diagnosed with coronary heart disease （CHD）（mean age 68.9 -4- 6.0 years） referred for treadmill exercise testing （TET） for clinical reasons were included in the study. They were asked to complete a questionnaire for clinical characteristics information on age, sex, history, exercise habits, medications, the original VSAQ and the modified VSAQ. We investigated the relationship between exer- cise tolerance in metabolic equivalents （METs） estimated by VSAQ and that obtained by TET. Results The METs by the original VSAQ and the modified VSAQ did not difference significantly （P = 0.528）. The modified VSAQ scores were significantly correlated with the METs oh- mined by TET （r = 0.819, 95% CI： 0.7534）.873, P 〈 0.01）, and the scores of original VSAQ also correlated with the METs by TET （r = 0.804, 95% CI： 0.7454）.854, P 〈 0.01）. The Bland-Altman graph analysis showed few values outside the limits of agrcement, suggesting good precision between the METs estimated by questionnaire and the METs obtained by TET. Conclusions The Chinese version of the VSAQ confirmed its validity and equivalence to the original version, especially when evaluating individuals with coronary heart disease and older adults. The results showed that the VSAQ is a valuable tool to assess the exercise tolerance.

关键词： Chinese Elderly Coronary heart disease Exercise tolerance Veterans Specific Activity Questionnaire

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Two-dimensional silica enhanced solid polymer electrolyte for lithium metal batteries

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Particuology 2024年第2期85卷 146-154页

作者： Zhihong Luo Weiyong Li Chong Guo Ya Song Mingxia Zhou Yan shi jing Xu Long Li Bin shi Quansheng Ouyang Jiao-jing Shao Guangmin Zhou School of Materials and Metallurgy Guizhou UniversityGuiyang550025China State Key Laboratory of Advanced Chemical Power Sources Zunyi563003China Graphene Materials Engineering Research Center of Guizhou Colleges and Universities Guiyang550025China Tsinghua-Berkeley Shenzhen Institute&Tsinghua Shenzhen International Graduate Schoo Tsinghua UniversityShenzhen518055China

Solid polymer electrolytes(SPEs)are promising substitutes for current flammable liquid electrolytes to achieve high-safety and high-energy-density lithium metal *** oxide(PEO)based solid polymer electrolytes have attracted increasing attention because of their excellent flexibility,manufacturability,light weight,and low-cost processing,while they often suffer from low ionic con-ductivity at room temperature,low lithium transference number and unsatisfactory interfacial resis-tance,which largely restrain their practical ***,two-dimensional holey silica nanosheets(2D-HSN)as the fillers,together with LiNO_(3) as the electrolyte additive,are introduced in a PEO/poly(-vinylidene fiuoride-co-hexafluoropropylene)(PVDF-HFP)blended polymer matrix to obtain a *** incorporation of HSN filler creates supplementary channels for lithium ion migration and lowers the crystallinity of the polymer,thereby facilitating the movement of lithium *** HSN-based SPE demonstrates higher ionic conductivity up to 3.7 x 10-4 S cm-1 at 30℃,larger Li+transference number close to 0.34,and more stable lithium plating/stripping than that without the fillers,and HSN can promote the formation of more stable solid electrolyte interphase(SEI)*** as-assembled LiFePO4||Li batteries deliver a high specific capacity of 159 mA h g-1 with the capacity retention of 95.5%after 200 cycles at 30℃,as well as superior rate performance and cycling stability compared to that using the blank SPE.

关键词： Vermiculite nanosheets Two-dimensional silica Solid polymer electrolytes FillersLithium metal batteries

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